Cool but Inefficient

""All right, yeah, it get six miles to the gallon on the highway, and three miles around town... y'know, the air conditioner doesn't work so well, and it's not very comfortable, um... but I just look so damn good in it, y'know what I mean?""

- Clem, Reno 911!

In the future we will have Ray Guns, space-food and all other manner of things replacing current day technologies. Sadly, they will also be far less efficient than what we have today, raising the question of why people invented them in the first place. Sometimes they don't work as well as what we already have, sometimes they work as well or better but require too much additional work, sometimes they're just annoyingly prone to Phlebotinum Breakdown.

Such technology is never useless in the show or movie's universe, and seeing it in action defines this trope. Sometimes its shoddiness serves to add drama to the plot; at other times, the only reason for it being there is to look cool and futuristic.

This is not in the least helped by a tendency not to do the research; futuristic rayguns also tend to lack some of the most common sense niceties of modern firearms. The most frequent mistake is the lack of a trigger guard, which would guarantee that phasers and blasters go off when incorrectly carried or set away. Just as common is a lack of anything vaguely resembling sights, a shoulder stock, or anything else to give you an edge over just firing from the hip. It doesn't help that almost no protagonist has any clue whatsoever about basic firearm safety, frequently keeping their fingers on the triggers, waving loaded guns around like feather dusters, and never, ever applying the safety catch, if there even is one.

Sci-fi spacecraft, in general, tend heavily to fall into this trope. Wings, fins, streamlined designs, and pointless projections stud the outside of spacecraft never intended to enter an atmosphere. Most modern portrayals are savvy enough to at least justify streamlined spacecraft. Star Trek leaves gaping voids in the middle of their spaceships, but in-universe, this is because the warp fields generated by the nacelles necessitate them being kept at some distance to the rest of the ship. Likewise, the Alliance ships in Firefly look nice because of their vertical ship alignment, but the placement of the engines is to keep the ships from ripping themselves apart every time they accelerate. Alternately, one could build along the lines of 2001 A Space Odyssey's Discovery.

Notice that this is Truth in Television, as several armies through history have used awesome but inefficient weapons to lay fear among enemy ranks. See Zack Parsons' book My Tank is Fight! for some examples.

Truth in History, also. For hundreds of years, long bows were significantly more dangerous than GUNS on the field of battle. Back then, guns were horribly inaccurate and had slow reload, while a longbow could be fired more times per minute than a gun by a large margin. Even a properly fired arrow could pierce armor that early firearms could not. Technological advancements, combined with deforestation, eventually led to the adoption of guns by armies. The greatest advantage of guns was always that you could train a man to use one in a span of weeks, where building the muscles and accuracy of a skilled archer took decades. Maybe those future weapons just haven't evolved enough? But then you'd think a lot of people would still be using boring old bullets... Damn you, Rule of Cool!

See also Awesome but Impractical, which is where there actually is a genuine advantage to using the stuff, but the added drawbacks are substantial as to limit its usefulness. Contrast Boring but Practical, as well as Awesome Yet Practical where the Cool coexists with the Efficient.

Anime and Manga

 * Tiger and Bunny has Good Luck Mode, a "super mode" that does fuck all when it comes to actually enhancing the title duo's abilities -- but doesn't it just look so cool?

Commercials

 * This Orbitz commercial. "Why didn't you just mail it?" "Because we have a hovercraft."

Comic Books

 * The Remo The Destroyer comic featured at one point (in the hands of the bad guy) a prototype gun, intended by the manufacturers to be a standardized field weapon, that fired a nuclear explosive. Blast radius? 5000 meters. Range of a shot? 1800 meters... maybe... with the wind in the right direction. Suffice to say, it didn't sell.
 * This was a real weapon[[http://en.wikipedia.org/wiki/Davy_Crockett_
 * In Fables, magical artifacts native to the Homelands were capable of powerful and varied effects such as the Vorpal Sword being able to cut through anything or the Mirror on the Wall being the perfect spying device while on the same plain. However they could not be mass produced and mundane weaponry was a serious threat to the Adversary's regime.
 * One of the stormtroopers in Twisted Toyfare Theatre built a three sided lightsaber. He ended up accidentally cutting his own hand.
 * Every Rube Goldberg Device from Rube Goldberg's comic strips. Even moreso because of the need to create the darn things in the first place.

Film

 * Sci-fi from Star Trek to Star Wars and everything in between tends to have spiffy, future weapons (phasers, blasters, etc.) if they're so inclined. For all their technology, these guns seem useless when you actually have to kill someone who matters. Guns shown before to vaporize inanimate objects now only leave a nasty burn or push people back a few feet. And that's disregarding all the situations where energy weapons don't work or are defeated by defenses that wouldn't even slow a bullet. Which is somewhat justified (at least for Star Trek) in that phasers have more than one power setting. Still, needing to shoot a man hiding behind a rock should be easy enough for something which should be able to shoot THROUGH it if you don't care what happens to him on the other side.
 * This is lampshaded in Star Trek First Contact. The borg bad guys can develop immunity to their energy weapons, but captain Picard kills two of them with holographic bullets fired from a holographic tommygun from a historic holodeck simulation. Even when they're not real, our guns are still better. Unless the drones simply hadn't adapted yet.
 * Star Wars perpetrates the same problems as Trek when it comes to force fields, most notably with forcefields replacing regular spacedoors. In this case, power failure would lead to explosive decompression of all landing bays. However, as Revenge of the Sith shows, there are typically emergency metal doors that quickly close in the event of such a power failure.
 * Perhaps the most garish example of Cool but Inefficient technology is the Buzz Droid Missile in Revenge of the Sith. A missile is deployed which tracks its target, flies ahead of the target and then explodes to disperse small droids which then must attempt to tear apart an enemy starfighter from the outside in. Exactly how this is more efficient than simply packing the missile with high explosive and letting it hit the target first is not explained.
 * Arguably, there are good reasons to want a missile which does no immediate damage to the target ship or its pilot and disables its target slowly enough to permit that pilot to eject -- it's just inexplicable why a Trade Federation ship on that particular mission would have those missiles loaded, or fire them in that situation.
 * IIRC, those missiles were designed for attacking capital ships. The droids would cut their way through the hull and disrupt the ship's systems from the inside. Why they were fired at starfighters remains a mystery, however, though most combat droids aren't particularly bright to begin with.
 * And, of course, the lightsaber, which, while lethally effective, suffers the same drawback that rendered metallic swords obsolete when firearms came along: its maximum effective range is one yard plus the length of your arm. Of course, it is more effective in the hands of the people that favor them, considering their extreme reflexes and their ability to reflect your shots back at you...but only because their enemies are using Frickin' Laser Beams instead of bullets despite knowning they can be reflected.
 * Also, as Darth Vader demonstrated in The Return of the Jedi, a light-saber in the hands of a Jedi or a Sith can be used as a ranged weapon, and a rather effective one.
 * Explained in Shatterpoint. Blasters are more effective than slug pistols against everything except a lightsaber, and nobody expects a Jedi to show up so they've abandoned conventional guns because of the Antidote Effect.
 * In Demolition Man, the plasma gun used by Simon Phoenix takes minutes to recharge; Simon uses it anyway, because he likes to see things blow up.
 * Took minutes to recharge after being in storage in a museum. Once it had recharged itself it was firing plasma bolts as fast as a pump-action shotgun would be firing slugs.
 * That was a nuclear powered railgun, it had to achieve fusion before use.
 * The Island featured weapons that fired barbed hooks, like a taser, used to stop escaped clones. Except the hooks were bigger and looked more painful, and the thing didn't give an electric charge to subdue the struggling victim, now in horrible pain from having two huge anchors shot into his skin.
 * Actually, this one may be justified. Since the weapon is presumably designed specifically to recapture escaped clones (who were created solely for their organs or child-carrying capabilities), the last thing you would want to do is potentially damage the organs or fetus by hitting it with an electric jolt. True, it is less efficient than a taser, but more practical for that situation, if only marginally so.
 * The hooks were at least strong enough to hold back a crazed football star (alright, technically his clone) so additional force to stop the targets would rarely be needed.
 * Acknowledged in Robo Cop, with the ED-209. The OCP Vice President Dick Jones mentions that he doesn't care whether or not ED-209 works, rather that it is marketable enough to be purchased by the military. ED-209, while deadly, is extremely faulty; it is unable to distinguish a surrendering "hostile" (really an OCP employee in a demonstration), thus brutally killing the man, its arm cannons can swivel enough to blast each other off, its large feet render it impossible to maneuver down stairs, it has a big vulnerable air intake at its front, and BOTH OF ITS HANDS ARE GUNS. What else did you expect it to do?
 * Designer Craig Davis claims he intentionally designed ED-209 to make it look like its fictional designers were more concerned about making it look cool than making it work well "just like an American car".
 * The novelisation makes clear that the guy was set up to be killed in OCP's cut-throat corporate environment.
 * And the 6000-SUX car, it's top of the list when a small time criminal demands a new car which has reclining leather seats, goes really fast and gets really shitty gas mileage.
 * Galaxy Quest lampshades this. The ship that they use is based off the ship from the Show Within a Show, and it's designed with giant fans, fire pits, and gratuitous explosions. Why? To make it harder to get from point A to point B, for plot purposes.
 * Taken literally with Back to The Future Part III, when Marty helps Doc with a massive steam-powered machine built in the old west - that creates a single dirty ice cube.
 * Avatar inverts this with the majority of human technology, Mini Mecha make a lot of sense on a planet with a poisonous atmosphere and 10-foot tall hostile natives.
 * Repo the Genetic Opera has translucent sheets of plastic for paper. One wonders how exactly you can read only the top page and not the stuff underneath.
 * In Iron Man, the arc reactor that powers Stark Industries is implied to be this, kept only as a publicity stunt, until Tony Stark is able to build a much more efficient prototype in a cave with a box of scraps.
 * Lampshaded in Without a Paddle when one of the murderous rednecks advises the other against using a meat cleaver to try to kill the main characters. "The cleaver is scary, but inefficient".

Literature

 * Halo EU emphasizes this point with the SPARTAN-II program. Of the 75 children conscripted, 30 were killed during the augmentation process and 12 were severely crippled. Factor in training time from age 7 to about age 20 and the costs of building and maintaining the MJOLNIR armor (each suit is said to be on par with the cost of a small starship), plus the very exclusive restrictions placed on candidates, and the Spartans are cool, but extremely inefficient, especially during the Human-Covenant War. Nonetheless, their effectiveness in ground ops is the only real edge the UNSC has for much of the war, but there are just too few of them to go around.
 * This is partly justified by the fact that the SPARTAN-IIs were originally intended to be used against relatively rag-tag human rebels, where their lack of numbers would not have been nearly as much of a problem.
 * The UNSC then rectified this with the SPARTAN-IIIs, who get more reliable (though somewhat less impressive) augmentation, have a wider candidate pool, and cheaper armor. They're more likely to survive the augmentation, have easier and cheaper (and slightly more ethical) recruitment practices, they can be trained a lot faster than the S-2s, their existence is secret, so no one can exploit their weaknesses like they have on occasion with the S-2s, and best of all,
 * In the Potter Verse, the wizards tend to insist on doing everything by old-fashioned means and by magic, even though modern technology would often work better even than the magic.
 * Given the relative ease with which wizardly means of communication (owls, fireplaces) can be tampered with, it's astonishing that they don't just use telephones and email. Eventually the series does attempt to justify this through a combination of claiming that large amounts of magic will interfere with electronics and that enchanting technology that's too modern makes Masquerade breaches far more likely, but still... And owls for communication, how can that be anything but Rule of Cool?
 * Rowling has explicitly stated in an interview that the reason for the Masquerade is more or less that a muggle with a shotgun will beat a wizard with a wand almost every time. Which is also explored in this Sluggy Freelance parody.
 * A better justification is just how old-fashioned and isolationist most wizards are even without the Masquerade. That, combined with magical interference and magic having a lot more immediate and overall versatility (it's hard to set fires with a garage door opener, or fix furniture with a gun), show a society that's really just beginning to modernize. The fact that they try to modernize and have a department for understanding muggle life and technology might also explain it. They don't seem to fully understand all of this.

Most of the magic-using folk are shown to be highly ignorant of the modern world. Magic has allowed their culture to stagnate at a far less-modern level; they haven't modernised because they haven't needed to. A lot of them pity people who don't live as they do -- leading to a broad spectrum of opinions ranging from 'ahh, bless!' to 'do what you like with them -- they are inferior'. Even Voldemort does not concern himself with 'Muggles' (they even have a derogatory word! How very White Wolf of them), just the domination of the magical community. The overall impression is of a self-important culture that thinks itself in charge; what would happen if the Masquerade were ever broken and the witches and wizards found out what the modern world has achieved in terms of death and destruction?
 * The wizarding world is also lagging behind in terms of human rights and regard for basic safety. No modern muggle society would dream of not immediately outlawing Howlers, for example -- even their use by a righteously indignant mother would be considered abuse, to say nothing of their use as hate mail. As for safety, it should be said that the modern Western society is arguably going too far in worrying over the safety of children at all times, but the sensible line might still not be where the wizards draw it (since that sometimes seems to be nowhere at all). In a narrative sense, all of these things exist in the stories because they make things more interesting.
 * That is specifically and deeply Averted in the Dresden Files -- and getting muggles involved is something akin to nuclear strike in the supernatural community, and has been even back when humans waved torches and pitchforks around. Now, with powerful weapons; broad communications and mobilization; and fast, effective, heavy-duty transport humans are a force to be reckoned with. A lot of technology will fail in the presence of powerful magic, but a bullet can kill a wizard or a gibbering monster just as easily as a ball of fire. (In the case of said monsters, sometimes many bullets.)
 * More directly, sparks and other special effects are a sign of inefficiency in handling magic. Harry remarks that, while his damaged-focus-based shield dripping sparks could look a little cool and his staff dripping  could look pretty impressive, all of the supernatural crowd knows that to be a sign of poor form.
 * Lampshaded in World War Z, where an angry veteran of the zombie war blames the loss of the Battle of Yonkers partly on the flashy, high-tech weapons used: Incendiary weapons and shrapnel were far less useful against zombies who could only be killed if their brain was destroyed. This is then subverted later on, where a number of energy weapons become the subjects of propaganda films which boost the morale of the surviving humans. Though they have no strategic value, they make a huge psychological difference.
 * The most effective weapon in the war turns out to be "The Lobotomizer"--a cross between an entrenching tool and a battleaxe, invented by Marine infantrymen.
 * One chapter mentions a kid on rollerblades, trying to fight zombies with a meat cleaver on a hockey stick. It probably looked very cool in his imagination. The actual fight didn't work out quite as well.
 * The Zombie Survival Guide cautions against many of the more photogenic resorts. Motorcycles, cars and guns are noisy, flamethrowers and machine guns are designed to combat targets that stop moving when their muscles are destroyed, Kevlar vests only cover the torso, and more. It's interesting to read that the person with the greatest chance of surviving is an unarmored man on a bicycle with a crossbow and crowbar.
 * In Arthur C. Clarke (Creator)'s short story "Superiority", one side in an interstellar war comes up with a series of cutting-edge technological breakthroughs. Unfortunately, they are rushed into production before the bugs are worked out, and the resulting fiascoes more than cancel out the military benefits. The last straw comes when a device to stretch space around a ship (putting it far away from the rest of the universe, thus making it invisible and untouchable until the device is switched off) turns out to subtly distort everything on board, to the point where the fleet's parts are no longer interchangeable. The enemy (which has continued producing tried-and-true warship designs) then overruns their logistically crippled fleet.
 * In the Childe Cycle stories by Gordon R Dickson, this trope is subverted by the standard rifles: They are basically extremely refined bolt-action rifles, powered by mechanical springs and levers. This is explained as they are the most reliable and tamper-proof weapon imaginable, as anything higher-tech opens the opportunity for higher-tech countermeasures.
 * Poul Anderson's The High Crusade took this subversion even farther: upon voyaging into space, medieval Earth knights find that the best weapon for sniper battles between space-suited infantry is their old reliable bow and arrow. It has no giveaway flash like a laser, it's a lot harder to patch a holed suit when there's an arrow sticking out of it, and the recoil sends the archer moving backwards after a shot, out of line of retaliatory fire.
 * In the Deathstalker series by Simon R Green, energy handguns take two minutes to recharge after one shot. They're actually used because they're inefficient; the monarchy banned and hid knowledge of bullet weapons, since they were cheap enough to be used in uprisings.
 * This can also be used with the cool technology being 20th century. In Neal Stephenson's Snow Crash, guns have become so dominant that everyone worth killing wears kevlar and uses metal-detectors. Anyone ready to use glass knives and bamboo spears can quickly qualify as the "ultimate badass". It is ultimately shown that these weapons aren't inherently superior, but are still the most effective simply because no one expects them. Only a handful of characters learn either lesson... but one who does leads to a Double Subversion.
 * The Martian Tripod machines from War of the Worlds. Yeah, they were scary and wreaked havoc on mankind, but their heat rays can only do so much damage at once. Something like an atomic bomb or similar would seem to be a more obvious and efficient answer. You'd think creatures composed entirely of brain would realize that.
 * As HG Wells assumed an 'atomic bomb' would involve some sort of continuously-burning explosive rather than a single city-shattering blast you can't blame him (see "The World Set Free").
 * A case of Science Marches On. Also the Martians didn't want to exterminate humanity, but harvest it. Weapons of mass destruction leaves just that, mass destruction. That's why they came here, to get away from their own destroyed planet.
 * In The League of Extraordinary Gentlemen, Mr. Hyde helpfully points out Lesson Three to the inhabitant of a Tripod - whilst the whole 'three-legged tripod of death' thing looks awesome, should something happen to one of the legs (like, say, a superpowered psychopath physically wrenching one of them off), then good luck remaining upright with only two.
 * Inthe original story they're tentacle likes structures, not leg-like ones.
 * In Dune, the onset of field-generator-shielding makes lasguns so Cool But Inefficient (firing a lasgun at a shield causes a small nuclear explosion) that nobody uses them. The fact that shields effectively stop normal ballistic weaponry as well means that all warfare needs to be conducted with swords. For that matter, even swords will be blocked by the shields if they are swung too fast.
 * It is a little surprising that, given the amount of religious fanaticism present throughout the novels, so few warriors ever sacrifice themselves by firing a lasgun at an enemy squad thus destroying many enemy troops at the cost of one. This is used only once (to this troper's memory) by desperate rebels against Paul's jihad forces (i.e. someone non-religious suicide-bombing a bunch of religious fanatics) in Paul of Dune. For that matter, the palaces of all nobles are protected by massive shields. Why not sacrifice one guy to destroy your enemy in one fell swoop?
 * The same religious fanaticism is why. Killing with nuclear weapons is so forbidden, the whole rest of the galaxy will jump on the offending House and destroy them. The first book notes that the lasgun/shield interaction is indistinguishable from a nuke and would suffer the same penalty.
 * There is an example of this being used, but only as a booby trap. Since the normally solitary Sandworms will swarm-attack any operating shield on Dune. nobody uses them in the desert. This makes it perfectly safe to use laseguns to probe for anyone trying to hide under the sand, right up until somebody just leaves an operating shield generator out on the sand....
 * The whole point of Tomorrow Town, the short story by Kim Newman -- an experimental community based on a 70's sci-fi vision of the future, full of impressive-looking but useless technology: 'nutritious' food pills that leave you hungry, modes of transport that travel at walking speed and often break down, a cleaning robot that's outclassed by any standard vacuum cleaner, and a Master Computer that can solve mathematics and technical problems but not the complexities of humanity and politics.
 * Every raygun, robot servant, health-enhancement device and motive-vehicle in Doctor Grordbort's Contrapulatronic Dingus Directory is made to sound impressive through Sesquipedalian Loquaciousness advertising, but is either completely useless or highly dangerous to the user (sometimes both).
 * In the first Honor Harrington novels a weapon is introduced that can bring down an enemy ships shields, which would be an in universe game-breaker, if its range wasn't so absurdly short that you're considered to be in 'point blank' energy range at roughly four times its firing range. And that doesn't even factor in the missiles which have orders of magnitude more range anyway.
 * She then proceeds to win an impossibly unbalanced fight with it. However, that is less because of the weapon than because it's Honor, who would really have preferred a full missile broadside instead, and she is quite annoyed when the developer attempts to use this event in their favor.
 * It is later revealed that the person who ordered Honor's ship outfitted with these weapons never expected it to be used in an independant deployment, and that the ship was just the testbed for using it as part of combined-arms tactics.
 * In a much later book, the Solarian League's Fleet 2000 program to modernize their fleet does provide some improvements in technology, but many of the changes are merely to make the tactical and astrogation displays more photogenic, which also impairs the actual usefulness to the SLN personnel trying to read them while in battle.
 * Similar to the Dune example, in Sergey Lukyanenko's Lord From Planet Earth trilogy, most weapons are rendered inert by neutralizing fields, resulting in armies armed with Absurdly Sharp Swords. Strange that no one thinks of using chemical or biological warfare, although given that said fields also stop destructive nuclear fission, fusion, and matter/antimatter annihilation, it isn't too farfetched to assume it also blocks these as well. Along comes a typical human male, who spent a few tours of duty in war zones on modern-day Earth, and almost immediately comes up with primitive weapons that still work in the field, such as an Absurdly Sharp Frisbee and an gun that shoots small versions of it powered by a mix of compressed air and a magnetic coil. Cue the horrified reactions of Human Aliens used to honorable duels, when one such frisbee takes a man's head clean off. Definitely a case of Humans Are Warriors.
 * In fact, the first book's Big Bad reveals that one of his scientists designed something similar to the frisbee, only for the Big Bad to order his execution and the plans destroyed.
 * These small disc-shaped projectiles also have an offset center of gravity and have the same effect as a hollow-point bullet (i.e. they bounce around inside the target's body, shredding organs).
 * A very literal interpretation in the Enchanted Forest Chronicles is the use of magic by wizards. Any lights or smoke that is not being used to produce the intended effect is excess magic that's being wasted. The more amazing and flashy their magic is, the less efficient it is, and thus the weaker their spells are. The deadliest wizards don't whirl away in a twinkling of light; they simply disappear.
 * That said, it takes a lot to get a wizard to resort to their very deadliest spells; they're a very theatrical lot who like their amazing, flashy spells.

Live-Action TV

 * Star Trek's got examples by the ton:
 * A Deep Space Nine episode centers around a firearm Starfleet was planning to use when their phasers wouldn't work. The weapon was quite versatile: The person using it could not be found by normal means, and it was modified with a microtransporter so that it could shoot through walls. Even though the gun was shown to be incredibly efficient, they found a way around the phaser problem, so all work on it was dropped.
 * Because the new weapon was probably vastly more expensive. It had a built-in transporter! All a phaser needs is a power cell - pretty bog-standard tech in Trek.
 * Except money doesn't exist in The Federation?
 * The TR-116 Rifle was dandy (the transporter and associated targeting sensor monocle were an add-on to make it the ULTIMATE sniper rifle), but a phaser is far more than just a gun (although they are rarely shown being used for other things). In addition to being used as a gun (with the added benefit that you could reliably disable a foe, instead of only trying to kill them), they can also be used as an emergency energy source for other devices, for heating objects, and for cutting or destroying various materials quickly and reliably. In addition, there's less risk of accidentally puncturing the hull of a ship (or something else you'd rather not puncture, like that big tank of poisonous and corrosive fluid behind the guy you need to kill) with a phaser than a slug-throwing rifle.
 * Star Trek has also shown that forcefields are the primary means of keeping prisoners in their cells. There's no indication that a solid door wouldn't work just as well and of course there's no reason they couldn't use both forcefields and physical doors, like shuttle bays do.
 * None of the hand phasers in The Next Generation had any visible means by which to aim. Admittedly, pointing the weapon at your target was often optional as the special effects department would just put the beam where they needed to regardless where the actor was pointing the prop. Apparently the weapons come with some kind of auto-aim.
 * Star Trek First Contact also features at least one Forcefield Window, though wisely covered with a shutter when not in use.
 * In Stargate SG-1, Goa'uld staff weapons are highly inefficient. Eventually, we're explicitly told that they're created for terror, not for efficiency; humans find firearms (or zat guns) more useful. One episode even features a demonstration for the benefit of rebel Jaffa.
 * Though it's worth making the point that both are lethal. In fact, the SG teams routinely got their asses kicked until they started using armour-piercing rounds. It became clear that given both sides knew their weapons inside out, the SG teams' only real advantage was the armour-piercers. Also, the P90 does not make a very good melee weapon, in contrast to the other main use of the staff, which was as a bokking-stick!
 * The only advantage staffs have is power, they're less accurate, lower-ranged and slower-firing. Maybe they could replace combat-shotguns, but they're not going to replace assault rifles.
 * The Staff Weapon was rather good for its' intended purpose, and so is the P90, but those purposes aren't the same. As O'Neill pointed out in one episode, a Staff Weapon is designed to intimidate the enemy as a show of force. The P90 is designed to kill the enemy as a demonstration of force.
 * To see exactly how the staff weapon should have been designed you should look at a very similar weapon carried by members of the Commonwealth in the TV series Andromeda. Like the staff weapon it is a long incredibly powerful energy weapon that can be used in melee combat. Unlike the staff weapon however this version is telescopic allowing it to be also used as a hand-held weapon; effectively removing one of the key disadvantages of the Goa'uld and Ori models.
 * Stargate also has an example of the impractical prison that works by shifting the gravity horizontally and turning a long room into a deep pit. It has no door, fails during a power outage and could be escaped from by having a friend lower you a rope. But, dammit, it looks so cool!
 * The Goa'uld also use force fields instead of glass for windows on their spacecraft, which they attempt to justify as being necessary because glass would not hold up under the strain. Of course, glass would at least try, unlike a force field in a power failure.
 * Do you think they ever tried a big lump of colourless sapphire?
 * Miraculously averted in Stargate Atlantis -- Ancient holding cells have an energy barrier but also, the common sense precaution of real bars... If only they'd been so sensible the rest of the time...
 * However, the cells aboard the Daedalus-class ships have doors held closed by maglocks... which can be hacked from the inside of the cell.
 * This troper suspects the 'electric lock' issue also plagued the Atlantis holding cells, although he's not sure.
 * A run-down bar in an episode of Firefly has holographic windows that don't even provide any sort of forcefield. This makes for the "window" is used as a parody/homage to the traditional cowboy movie barroom brawl, allowing the protagonist to be thrown through it without resistance. The advantage of making a hologram of something that's supposed to be transparent, though...
 * Apparently it's a very low-strength (electrostatic?) forcefield that stops blown dust and insects but a flying person can pass through without resistance.
 * It also says something about how often people go flying out that window that it's worth sticking a hologram/forcefield there instead of glass.
 * Is it just the glass that's holographic, or are the glazing-bars tricks of the light as well?
 * In a later episode there's a holographic set of pool balls which seem to be slightly less reliable than a real set. Presumably in both cases it was more about setting the scene, particularly in the window example which is at the beginning of the first aired episode which Joss explains in a commentary track was all about frantically trying to explain what was going on.
 * Laser guns apparently. One villain shows up with a fancy laser pistol that he uses to some effect, then it runs out of power partway through a fairly short fight. It's probably worth noting that neither most independent citizens nor Alliance soldiers bother with hand-held laser weapons.
 * Inverted in the reimagining of Battlestar Galactica Reimagined, which deliberately uses pragmatic old-fashioned technology. The Shiny-Looking Spaceships turned out to be far too vulnerable to hacking and were blown up right at the start. The choice of starship weaponry drew particular attention for its freshness and originality: it uses machine guns. (Gauss guns, actually, but still...)
 * Played straight with the cornerless paper. Sure, it looks cool, but how do you store large quantities? On Earth, we put our cornered paper in rolls, what do they do? Although this might be more Alien but Inefficent.
 * Spoofed in the Mystery Science Theatre 3000 episode "Terror From the Year 5000": The Observers tell Mike that they've evolved beyond food, and get all their nutritional requirements from a tiny pill. It eventually gets revealed that they have to eat ten large bowls of them each day.
 * In Doctor Who, the title Doctor is joined by the ex-time Agent Captain Jack Harkness who proceeds to show off his cool sonic gun which can even blow exactly square-shaped holes into whatever blocks its path, which impresses Rose, much to the Doctor's disdain. Ironically, its many extras make the gun run out of energy in a crucial moment, leaving the Doctor and his sonic screwdriver to save the day.
 * It also replaced the bits afterwards, let's see a sonic screwdriver do either of those.
 * Blakes Seven had a weapon called the IMIPAK (Incipient Molecular Instability Projector And Key), a ray gun which induced incipient instability in the molecular structure of the target, after which you have to whip out and activate the Key to convert it to actual instability and thus destroy the target -- except that if the target is a living being and noticed you firing the gun at him, you never get the chance because long before then, he's zapped you with his own less acronymic but far more practical weapon. The IMIPAK might just about work as a stealth-based threat, but as a practical sniper weapon a simple club is probably better.
 * Some of the myths tested by the Myth Busters result in builds which fall into this category. (Those builds that don't qualify for this trope usually fall under Awesome but Impractical.) One of the best-known examples is the Lead Balloon--sure, you can build a balloon out of lead foil and have it float, but aluminum foil is stronger, lighter, safer to work with, and easier to get a hold of.

Tabletop Games

 * Likewise, Traveller uses good old-fashioned slug throwers (guns with bullets) even in far future society. There are lasers and plasma rifles, but good old-fashioned guns are as good as the former, and the latter are big and heavy and require battle armor to use.
 * Warhammer 40000 is in love with this trope, although it has some spectacular cases of boring but practical as well. Huge spaceships made to look like cathedrals? We got them. 300-meters-tall walking robots with castles on their shoulders? Elite close combat troops armed with chainsaw swords and 'shuriken pistols'? Tanks with guns so big they have other, smaller, guns strapped to them? Armies made up of 95% Cannon Fodder and a few good units and vehicles? Hordes of unarmed civilians supported by about 6 daemons? Oh boy, do we ever got them. Some armies even go as far as to make up reasons why these things have to be like this. For instance, the Chaos Marines (badass evil army whose cannon fodder is capable of withstanding a black hole) Codex explains that they only have weird symbols on walls and sharpened teeth because they feel cooler when they do. Also, asking them WHY they are evil is answered with "why not?" The Imperium of Man, meanwhile (they of the giant cathedral spaceships), lost all knowledge of why their technology works so long ago that a religion has built up to fill the void. They go and make everything super-ornate to please the "Machine Spirit" who animates their technology and think that if they lay off the pomp, everything will break.
 * It should be noted, that nearly all cases of this trope are very well justified in-universe.
 * It's also worth noting that the standard sidearm for military officers of the Imperium is a fully automatic armor-piercing mini-rocket launcher.
 * Larger weapons in 40K tend to take this to ridiculous extremes, as do alien weapons. The assault cannon is more or less an armor-piercing rocket-launching minigun, Necron gauss weapons strip the target's molecules away layer by layer, allowing them to punch through the heaviest armor as well as grant them the name "gauss flayers", chainsaw swords are ubiquitous among Imperium forces from longsword varieties to types longer than their wielder is tall, the larger Imperium vehicles don't so much fire a cannon as they do a broadside, and then there's the Shokk Attack Gun...
 * Well, then there are the guns that shoot plants, clouds of micro filament wire, giant death guitars, laser miniguns, and it just gets better.
 * Better yet, the Eldar and Tau take those insanely huge tanks, and make them fly (or at least Hover Tank).
 * The Space Marines, Super Soldiers taken Up to Eleven are an example of what happens when an entire faction is this trope. They have bullet-proof chests and corrosive saliva, can live on a healthy diet of concrete and metal, wear Powered Armor better than most tanks, have lifespans in the centuries or even millenia, land on a planet via drop pods jettisoned from an orbiting vessel directly to the surface without slowing, and have weapons including but not limited to aforementioned automatic armor-piercing rocket launchers larger than an average person and hammers capable of killing an Eldritch Abomination.
 * And that isn't even getting into the Chaos Space Marines, whose ranks include such delightful characters as Obliterators, Marines who've spent so much time in the Warp that they've fused to their armour, Plague Marines, Marines "blessed" by Nurgle with every disease in existence to the point where they're in so much pain they can't feel any other pain, and Noise Marines, Marines that make their enemies' heads explode with The Power of Rock.
 * Pretty much everything in the 40K universe operates by the principles of Rule of Cool and More Dakka (being the Trope Namer for the latter); with realism chucked right out the window at every opportunity.
 * On the other hand, the Imperial Guard is known for fielding tonnes of less elite, and lightly armed and armored infantry - humanity's numbers in 40K are at least in the trillions. They may have a laser gun, but in 40K, said laser guns' lack penetrating and stopping power against most of enemies of the Imperium(then again, said laser gun still has greater penetration than most modern guns, it's only Cool But Inefficient versus the incredibly powerful enemies you might run into in the 40k universe), its redeeming traits being very reliable, easy to maintain and make, (not to speak of that you can recharge the magazine by placing it in the sun or somewhere else that's reasonably warm which actually makes them Awesome But Practical) so you can arm those trillions.
 * The Tau are actually fairly practical (at least in comparison to the other races), the only real problem being their Crippling Overspecialization in ranged combat.
 * They are aware of this and hire Kroot mercenaries to act as close-combat specialists.
 * Kroot are generally used as pathfinders and scouts than close-combat specialists, though. The tau actually frown upon species/societies that glorify or specialize in close quarters fighting, and the kroot have the additional issue of eating their enemies after killing them. Tau get bonus points, however, because they use their advanced technology to the fullest extent. Their most basic infantry wear armor on par with that of Imperial Guard stormtroopers, and their weapons are generally Awesome Yet Practical.
 * In the D20 RPG based on The Wheel of Time series: Shocklances, supposedly the front line infantry weapon from the War of the Shadow, are statted out with huge damage, but only eight shots. They're not reloadable, either. Each shot comes back on its own, after an hour.
 * To be fair they kinda pulled that out of their collective asses. When a shocklance actually does finally show up, or rather its pistol variant (Shocklancette?) it has immense range, no ammo limits and can Stun or Kill without triggering the "i am using magic" alarm that channelers have in the back of their head.
 * The Humongous Mecha from Macho Women With Guns is described as "...dominated the battlefields until people realized what a ridiculous idea they were."
 * In the Iron Kingdoms Colossals were giant mechs that were made into smaller warjacks as they proved inefficient after the repelling of the Orgoth threat.
 * The Battle Tech universe has a long and intricate history that attempts to justify why they bother at all with giant robots - in this case it's because of the flexibility of a humanoid form, and the durability of their modular design. They're regularly used in civilian work as well, so there isn't a shortage of competent pilots.
 * The old Star League got past this trope and ended up nuking themselves back to the pre-industrial age, so most 31st century combat is deliberately kept like this to limit collateral damage. The rare incidences where lostech nukes show up demonstrate why this is a good thing.
 * This is a very inaccurate description of what happened, technologically, in the Battle Tech Universe. The Star League collapsed about 3 centuries prior to the game's original starting point and the Successor States ended up heavily damaging their own military infrastructure, yes. However, they did not nuke themselves back to pre-industrial levels, in general, they only dropped back to 23rd to 24th Century technology, from the high point in the 28th Century. Nuclear weapons were not one of the technologies that were lost, either, the Inner Sphere was simply so shell-shocked by the devastation that unrestrained WMD usage had caused that they voluntarily stopped using such weaponry, even though they still had easy access to it.

Toys

 * Gold Plastic Syndrome is a fairly infamous term, which refers to certain Transformers toys. Essentially, certain batches of metallic plastic from 1989-1998, usually used in big, impressive toys, tended to degrade over time and fracture with ease. The end result? Pretty-looking, shiny toys that would shatter while being taken out of the box.

Video Games

 * Half-Life 2 equipped the player with the Gravity Gun, which is basically used to hurl garbage at people (instead of, I don't know, bullets). Of course, this is a lot more fun than it sounds, and you're unlikely to run out of ammo. On the other hand, Alyx makes a point of saying that the Gravity Gun is a tool used for carrying large and hazardous material, and wasn't meant as a weapon.
 * In the Ravenholm level, it can be useful for saving ammo, as the zombies can only melee, and if you get yourself a radiator, a saw, or a razor blade, you can hold your ground against them without firing a shot. Now, against the fast zombies and headcrabs on the other hand...
 * The ending of the Half-Life 2 and the beginning of Episode 1 has the gun become super charged, and allows it to kill enemies by itself, but it is still limited by range, which can be a hassle when you have soldiers attacking you from a distance. You can't loot their weapons either, as guns in the Citadel vaporize when dropped.
 * In the last battle of Episode 2, the Hunter can soak up all the damage of all your conventional weapons combined, even the rocket launcher. But if you run them over with your car...
 * Arguably everything but the Shotgun, Magnum and Railgun Sniper are this. Most of the weapons have a horrible spread, for example the Combine Assault rifle which sprays its bullets all over the place.
 * This troper has regularly used the Gravity Gun in order to create a form of 'moving cover'. An improvised Riot shield made of an iron desk, for example.
 * In Zone of the Enders 2, the Vector Cannon was just about the coolest weapon in the game. Unfortunately, outside of a few isolated instances (destroying the battleship engines, the shield around Aumaan and as a spectacular ending to the final Anubis fight if your aim was good), the weapon was practically useless due to its long recharge time, the requisite that your mech's legs be touching the ground or another stable surface during the charging, and the inordinate amount of subweapon energy consumed by firing (though the latter was negated if you played as Naked Jehuty, which had infinite subweapon energy).
 * Really, the Vector Cannon was never meant to be used in combat at any point, and existed solely for story purposes. However, it should be noted that a 20 second charge period for a weapon that could destroy anything in its path is pretty nice. In an actual combat situation with backup (Rather than a one mech army) such a weapon would be devastating if protected properly.
 * Inefficient, sure, but fun. If you give the player an instant death weapon that worked every time, you break the game. If you make it only usable some of the time by limited ammo, you create Too Awesome to Use. But if you simply make it hard to use, the moments where the player manages to utterly negate a combat by deploying the stupidly large artillery gun before the enemy can get their act together will stay with them long after they've forgotten everything else in the game.
 * Final Fantasy XII gives you The Treaty-Blade and The Sword of Kings. These swords have the power to cut Nethicite, but, more importantly, have been bequeathed by the Gods themselves. Naturally, these swords'll be amazing, right? Wrong. They each have 30 attack. To give you an idea, the maximum attack a weapon can have is 150 - the kind of weapon your fighters will have at the time will have between 50 and 70. Admittedly, the swords good for dodging, but other than that, it's basically there to look pretty.
 * Hymir's Finger in Drakengard is a literal BFS in a game which has done a good job of keeping the weapons relatively realistic, or as far as one can in a medieval-fantasy world. It is long enough to qualify as a jousting lance, and it does a hell of a lot of damage, enough to mistake it for the Infinity+1 Sword. Cool, but it takes forever to swing. If you time your attacks right, you can wipe out whole squads of enemies, but the sword requires too much work to use properly. And the actual Infinity+1 Sword is so much better.
 * It's mainly meant for the more challenging side missions/weapon unlocking (like the one where you have to kill 150-odd zombies) due to the fact that once you get a combo started, it's hard for anything to get near you.
 * The Crusader games feature dozens of neat little death effects caused by exotic weapons that use molecular inhibition fields, chemical catalysts, microwaves, and so on... but when you get down to it, you're better off with the automatic shotgun and the rocket launcher, if only because there's a lot more ammo.
 * Also, unlike the exotic weapons, standard ballistic weapons such as the automatic shotgun or submachine gun did not completely destroy an enemy's body, meaning you could search them for items and ammo afterwards.
 * In Civilization 4: Beyond the Sword, the entry in the in-game encyclopedia for the assault mecha in the Next War official mod lampshades this, stating that the widespread use of the inefficient, unstable war machine instead of giant tanks is a result of its cool appearance, since awed politicians would be more likely to grant a budget to impressive-looking projects.
 * However, it does mention that they were used more for subduing rebellions from the fear value- whereas the true best unit is a massive tank.
 * Cool but inefficient describes all the Big Guns in Fallout 3. Though they all have a higher damage rating, they either have a high spread or low rate of fire. The Rock-It Launcher is the coolest of the bunch, and relatively efficient in that it can load any random junk and deal a hefty punch with it.
 * However, the Rock-it Launcher is among the least efficient weapons because its ammo adds to the weight you can carry. All other weapons have weightless ammo.
 * The Gatling laser is like a laser minigun and is nearly the highest damage weapon in the game. But it is incredibly inefficient due to rarity of ammo (you can buy ammo for it eventually which costs alot), near inability to land critical hits (a one-shot critical on a target's head will usually kill it, even from a small weapon; and big guns have a painfully low critical hit chance), and the gun breaks down fairly quickly from extended use: Each shot reduces a weapon's condition which lowers its damage per shot. The Gatling laser has a blindingly fast rate of fire which also makes it deteriorate blindingly fast.
 * The Alien blaster is a unique weapon you can find that has an extremely high base damage and a 100% chance to land a critical hit with every shot. However it has an extremely limited ammo supply that cannot be replenished. Also, every shot will make it deteriorate by a sizable chunk until it becomes useless and the gun can only be repaired by NPCs which is expensive and very few NPCs can repair it up to 100% of its condition.
 * A suit of the most advanced pre-war T-51B power armor can be found that has the highest damage and radiation resistance of any armor type in game, but it is the only one if its kind and if you take lots of damage, can only be repaired by NPCs for a very high price.
 * The Experimental MIRV is a missle launcher that fires 8 mini-nukes at once. However, mini-nukes are hard to come by.
 * And in addition, you could get caught in the blast. And the chances of actually needing to fire 8 mini-nukes in one shot are pretty low.
 * The Krimzon Guard Hellcat cruisers in Jak II: Renegade easily qualify. On first sight, they're a flying tank, what's not to like? ...They're so large and slow they're nearly impossible to miss, they maneuver like a quadriplegic cow, their gun is no deadlier than that on the far nippier Guard speeder bike, and if you steal one, you'll piss off every Guard in the city. Just as an additional bonus, these annoyed Guard will come after you on speeders, crash into the back of your stolen Hellcat, and thoughtlessly explode, taking you down in an antigrav pileup... and if you're going along the ground, expect to have a dozen of these bikes hanging over your head raining fire while you try and fail to steer it around a corner without scratching the paintwork. That said, an upgraded version becomes Awesome Yet Practical in Jak III, because this one not only flies far better, but also has one of the most beautiful smart-bomb effects in the universe.
 * The Unreal series has several weapons which are potentially more harmful to you than the enemy (Razorjack/Ripper, Biorifle), and a Gatling gun (Minigun) that depletes your ammo after a few seconds.
 * The Razorjack can become Awesome Yet Practical with the right usage, especially as each ammo pack for it is worth almost half its maximum ammo limit (and is added around as regularly as ammo for other weapons in a lot of cases). This also applies to the Biorifle if you get armour that makes you immune to to acid damage.
 * Metal Gear Solid 2 features giant battleship, which despite being sleek, enormous and carrying a whole complement of MGs, is worthless, as says.
 * And in Metal Gear Solid 3, Ocelot carries a revolver with detailed, ornate carvings...which, as Snake is quick to point out, offers him absolutely no tactical advantage unless he wants to sell the gun as a collector's item.
 * Castlevania games preceding Symphony of the Night often have a pocketwatch as one of the subweapons. It stops most non-boss enemies from moving for a few seconds, but almost any time it appears, it eats 5 hearts instead of 1 like the other subweapons do, except in Haunted Castle where it only consumes 2 hearts.
 * And in SOTN itself, it's totally useless, since all but the weakest mooks are immune to it. When Richter uses it in an Item Crash, it looks pretty badass, though, and is even capable of a (weak) attack in this mode.
 * You can use it to kill the Doppelganger boss though.
 * The above statement is not quite accurate: the pocket watch freezes most low level mooks (including those annoying medusa heads) slows down a large number of higher level mooks, and does work on several boss type enemies, or at least their projectiles. By the time you get halfway through the game, this is the best subweapon to have, since the other weapons, whose sole purpose is to deal damage, will be pitifully ineffective before reaching the inverted castle. The main problem is the 20 heart cost to the item, which is a small price to pay if you need to pass through an area swarming with medusa heads without frustration.
 * The STALKER series has the Gauss Rifle, an incredibly powerful weapon capable of killing nearly anything in one hit. On the downside of things, it has an incredibly low rate of fire, the ammunition is rarely found, and the few you can acquire are in such poor condition you only have a magazine or two worth of shots before it breaks.
 * Clear Sky dumbs it down even further by turning it into a prototype weapon that can only damage one specific enemy. Using it on the horde of fanatical mooks between you and him only gets you killed, very quickly.
 * Call of Pripyat compensates by making the Rifle a genuine one of a kind weapon which you pry from a miniboss's dead hands. But you need to go through a rather lengthy series of sidequests in order to make it usable, and once you can use it, the repair cost alone is worth a couple high quality artifacts, and you only get 10 shots for the cost of another artifact. Even better, the damage is now low enough that certain mutants will usually survive more then a direct hit, and some special Mooks in the end-game level can take a round to the chest. When they attack in packs of 6 or more and you can only fire one round every 3 seconds, the Gauss Rifle starts to become a a cool looking liability. It does have the best handling of any sniper rifle, which can be suprisingly useful, and it's by far the best choice for the only sniper mission in the game. It's still inferior to the VSS Vintorez and/or Dragunov SVD in most cases though.
 * Prototype's Snap-Kick Launcher. Basically treats anything smaller than a Leader Hunter as a soccer ball. Now if only a single maxed Musclemass boosted Snap Kick would just send that annoying supersoldier to his death rather than having to go after him to repeat the process.
 * Dirge of Cerberus Final Fantasy VII has the last level as Chaos. Chaos himself is very useful. All of his abilities are upgraded, and he uses the only weapon stronger than the Ultima Weapon. The thing is, the enemies are designed specifically to handle that weapon. That means, while your new melee combo is fancy, about twice as many hits in half as much time, and ends with a neat little mini-explosion, you're never going to hit anything with it. Even if you get close enough to try, you'll be pumped full of lasers, and the combo will be interrupted.

Web Comics
"Mell: Catch me if I'm wrong, but this looks like an energy weapon that loads like a flintlock pistol. This crazy moon crystal drops into the chamber, it goes poom, and a mean little laser shoots out. Thing is, it doesn't work as good as a normal gun. What's awesome is this gun is like you! Like you and Helen and ! It's totally mind-blowingly brilliant, but on a common-sense level it's dumb as a box of rocks!""
 * Averted in Schlock Mercenary, in which it is specifically mentioned that conventional firearms are frequently preferred, as they are less likely to cause Explosive Decompression in an on-ship fire fight. Schlock himself uses a massive antique of a plasma gun instead of far more efficient modern handguns, specifically for the glow in the barrel and the ommmmmmmminous hummmmmmmm as it charges.
 * Not to mention that Schlock cannot use a normal handgun to fly.
 * He has also been forced to leave it behind on several missions where he was warned that firing it would probably kill everybody aboard the station they were on.
 * At one point Schlock obtained a pair of impressive BF Gs from his enemies, then sawed off half the barrel to make them fit within his mouth and triple wielded them with the plasgun. The result was quite intimidating, especially to anyone who recognized how likely it was to blow up in his face.
 * Cited and made symbolic in Narbonic:

Western Animation

 * Lampshaded in the Batman Beyond episode "Shriek", where a sound expert demonstrates his powerful sound weapon to the corporate head, Derek Powers. The inventor finds he has a tough job selling his technology when Powers notes that for regular tasks like demolition, conventional tools like dynamite are just as effective and cheaper than some exotic new technology.
 * Also subverted in the famous Jonny Quest episode, "The Robot Spy". In that episode, Quest is working on a new weapon called a "Para-Power Raygun", which, he hopes, gives a practical new military option: the ability to paralyse enemy war machines by removing their power from a distance, thus allowing them to be captured intact, or at least neutralize mechanized units efficiently. However, the gun is used to shoot down the robot, and destroys it. Quest is disappointed, considering that, in being that destructive, the gun is merely an exotic artillery piece that's impractical considering the external generator involved.
 * In the Codename: Kids Next Door episode "Operation: T.R.I.C.Y.C.L.E." the KND attack the Tommymobile by using the biggest ketchup bottle ever seen. The kids at the moon base drop ketchup on it using a giant hand to slap the bottom of the bottle. It looks awesome, but does absolutely nothing. It's immediately lampshaded by one of the operatives attacking the bike from a plane.
 * "Who decided ketchup was a good idea?!"

Real Life

 * Companies have always been sending spam everywhere and to everyone to boost their profit, using the infamous spambots to do so. Recently it turned out a bunch of Chinese people could do it cheaper and more efficiently.
 * Likewise with large expensive robots to automate some of the boring drudgery in molecular biology, protein purification etc. A bunch of Chinese people can do it cheaper. Apparently two European people with a multi-pipetter could also do it cheaper, but it's easier to get a million Euros for a machine than for 15 years employment.
 * The above story Superiority is based on the escapades of Nazi Germany during World War II. Late in the war, the Germans tried to develop "super weapons" to turn the tide of the war.
 * The Vengeance weapons (one of which, the V2, killed more slave workers than enemies)
 * The Me-262 (the first jet fighter in active duty, which arguably could have affected the course of the war if the Germans actually had the fuel to power them or the time to train the pilots properly). Hitler actually further slowed down the production of these, because he wanted them to be bombers instead of interceptors.
 * Not to mention its engines required a complete overhaul or replacement after 12 hours of operation.
 * Plus its slow spool-up time made it surprisingly vulnerable while still on the ground.
 * The Me-163 (a rocket powered fighter which only shot down a grand total of 7 B-17s and, since the fuel it used was both explosively unstable and toxic, ended up killing more of its pilots than enemy pilots).
 * The Sanger Silbervogel (an unbuilt orbital bomber which was to bomb the US, as well as launch by using a large cluster of V2 engines to hurl it down a track to accelerate to a velocity to get it into orbit, and if that didn't kill the pilot, he'd simply burn up on reentry).
 * An explosive-driven sonic cannon that would use compressed air blasts to shoot down planes-- and had a range of a few dozen meters.
 * The P 1000 Ratte tank. The '1000' was to be the tank's weight, in tons. To compare, the largest tank ever built, the Panzer VIII Maus, another Nazi wonder weapon weighed in at 188 tons. If you want an idea of how the thing would look, just imagine a Baneblade from Warhammer 40000, and you wouldn't be far off (actually the P 1000 would've even bigger than the Baneblade, which is described weighting around 500-700 tons depending on the source). The tank was to have two 280 mm naval guns for main armament, with one 128 mm anti tank gun, two 15 mm autocannons, and eight flak guns. It was also to be powered by diesel engines which were used in U-Boats. The thing would have been a disaster. As slow as an arthritic turtle, lacking in anti-air defenses -- target practice for B-17 bombers. Even if the thing was able to defend itself from such attack, all you'd need to do to stop the tank in its tracks is knock out the enormous convoys of fuel tankers it'd need constantly following it. Albert Speer canceled this and the even larger P 1500 Monster, which would at least have been the largest self propelled artillery in history.
 * Even the Maus was impractical, barely faster than those things from WW 1, too heavy for most bridges, and too big for trains.
 * Schwerer Gustav and Dora. Two 80-cm rifled artillery guns, each weighing over 1000 tons and firing 7-ton shells. They required twin sets of parallel train tracks to even move around, which sometimes had to be built in front of them. They were designed to be used against the Maginot Line, so they were rendered pretty much irrelevant very early in the war, but they each actually saw action in the Soviet front. However, the enormous cost of building, arming and fueling the guns was way out of proportion to the amount of damage they ever did. Still, the guns were arguably useful as some targets in the Siege of Sevastopol were literally invulnerable to all other types of artillery besides the enormous 800mm guns, such as the "White Cliff" ammunition magazine located 30meters under the sea, with at least 10 meters of concrete protection. As such they could be said to have played a crucial part in bringing a siege that was tying up valuable units needed elsewhere to a quicker conclusion.
 * Some German general actually called Dora a useless state of the art.
 * Perhaps the ultimate in ridiculous Nazi superweapons is the Sonnengewehr, or "Sun Gun": A 100-meter wide magnifying lens made of metallic sodium orbiting the Earth that would focus the sun's rays and vaporize entire cities like anthills. A crew of astronauts would operate the whole thing wearing magnetic boots to overcome microgravity, with onboard pumpkin patches providing food and air. It never made it past planning stages.
 * You don't even have to look at their superweapons, but just as their regular tanks. Until Speer took over, every time the engineers came up with a new improvement in a tank design they would change the production line. While in theory this resulted in better tanks, in practice it was a mess because a unit could have tanks that didn't have interchangeable parts, making logistics a nightmare, even though the tanks would supposedly be the same model. Making this even worse was the German tendency to develop machines that were "more efficient, more elegantly designed, and needing five times as many parts". The Allies adopted a more logical approach, allowing proposed changes to accumulate until there was enough to justify a new model, and keeping things as simple as possible.
 * The Fliegerfaust was to be used as a personal anti-air rocket launcher that launched nine rockets at a time. It never saw combat use since its spread was too great and it never reached the desired range. Sanya likes it though.
 * The Nazis weren't alone in their crazy plans.
 * The Allies once tried to develop a large aircraft carrier made mostly out of frozen mulch. That's right, a gigantic ship made of icy wood pulp. It was designed to be much more resistant to German torpedoes and other hull breaches, since a block of frozen wood pulp is surprisingly resilient.
 * Well wood pulp impregnated ice is insanely tough stuff, the key point would be that since ice and wood float, they could make the hull several feet thick to facilitate it being torpedo proof. While they did build a proof of concept scale model, they realized in the process that it would be insanely expensive and time consuming to make, plus the war was ending by the time they could have gone forward with construction.
 * Another example of bizarre weapons on the Allied side is Walther Christie's ...unconventional... contribution to airborne warfare.
 * It should be noted that Christie, while he had some goofy ideas, also was a genius in armored vehicle design and his Christie suspension was used in some of the most successful tanks of WWII, including the T-34 and the Crusader.
 * The Soviets in turn, featured swimming and airborne tanks (which however, due to weight constrains, proved to be too lightly armed and armored to be useful, though in the context of behind-the-lines partisan warfare for which the tank was intended, those factors were not actually that much of a problem) as well as the MiG-3, an interceptor only effective at 3km altitude or higher (useful against high-altitude strategic bombers, but the Germans never managed to make any).
 * It is an old saw that the M-16, for all its precision, is not remotely as reliable as the less-accurate Russian AK-47 (as aficionados will point out, a properly-maintained M-16 works very well, and a AK-47 -- not a knock-off -- with good-quality ammunition will shoot quite accurately; however, this remains the common perception).
 * Most of the focus in the discussion was the Vietnam war, where most of the problems with the M-16 were because of several issues: First, it was put into production way too early (as such they were basically using a prototype,) they said the gun was self-cleaning (which it wasn't) and therefore didn't distribute any cleaning kits, and the casings were packed with the wrong kind of propellant. All this combined with the harsh conditions soldiers had to drag them through lead to a slew of reliability problems.
 * The Persian scythed chariot was an average war chariot with sharp blades mounted on the axles; the crew just had to plow through the crowd and the scythes would cut in half everyone within 1-2 meters. It wasn't very efficient, as casualties could be greatly avoided by letting it pass, and it could pretty much only work in open flat country with enough room to maneuver, but damn, there was nothing as awesome as seeing dozens of soldiers sliced by its might!
 * This was demonstrated on the "Persian Immortal vs. Celt Warrior" episode of Deadliest Warrior, where the Celt warfare experts simply said that it's pretty easy to jump over the scythe, which is exactly what the Celt warrior does in the final simulation before using a sling to take out the chariot driver..
 * Chariots themselves fell out of favour eventually, something about being big, relatively slow (compared to a man on a horse), requiring said flat surface, and not being able to charge head-on at infantry.
 * The scythe chariot lasted through no more than one engagement with Alexander the Great. He invented the Mousehole, a simply modification to the formation of his heavy infantry that allowed them to easily trap one when it was driven at them, then kill the driver. Combine that with the fact that heavy infantry was already pretty resistant to the damn thing...
 * Flaming. Pigs.
 * Anti-Tank. Dogs.
 * You can't say that the germans weren't responsible of shooting the dog.
 * Bat Bombs.
 * This is more of a case of Awesome and Practical as the test proved extremely promising, we had thousands of bats available, and the only reason the project was canceled was that they decided it would take too long for the weapon to be battle ready, even though a complete bomb was tested on a mock Japanese Town. Official name was Project X-Ray.
 * Pigeon missiles.
 * One can add war elephants to this, once the Romans worked out how to stampede them into Hannibal's own armies.
 * Can they ski?
 * War elephants pretty much define this trope in general. IIRC, that's part of why people stopped using them.
 * Chainsaws in general. Yes, they're very awesome and can hack through trees and such, but try swinging around something that's big, loud, heavy and just plain messy and you'll probably severely injure/kill yourself. Not to mention that, should the chain get jammed or caught on anything, it can snap and whip out into your face.
 * Chainsaws are Awesome Yet Practical if your cutting up firewood or trimming trees. One has to ponder how many tropers realize the original purpose of the chainsaw was not hacking zombies.
 * If you have a micromanaging boss, they probably obsessively order you to do your job in a Cool but Inefficient fashion, while bitching about how your productivity sucks.
 * Ladies and gentlemen, I give you the Thunder and Maadi Griff .50 BMG handguns. Yes, handguns.
 * I see your .50 BMG and raise you .600 NE. Zeliska, a handgun that uses ammunition designed to kill a charging elephant in a single shot.
 * One trick that Chinese archers used was to tie small fireworks to their arrows. This would increase the range and speed of the arrow, but make it unbelievably inaccurate. On the other hand, this just added to how terrifying it was.
 * The Koreans, in turn, piled them into a wine rack with wheels, and turned it into a truly terrifying artillery piece.
 * The virtues of lasers as a weapon system are heavily debated, with innumerable threads on forums, the old Usenet, etc. filled with heated discussions of their flaws, virtues, and relative expense versus shooting bits of metal at high speed. See Kinetic Weapons Are Just Better.
 * And bows were better than guns when the latter first appeared, give it time.
 * One plausible use for lasers might just be to take advantage of the fact that a laser beam is just coherent, high-intensity light and blind your target(s). As in, quite possibly for good. Of course, that'd still be a far cry from having a proper futuristic ray gun. More of a terror weapon, in fact...
 * To the point, in fact, that the Geneva conventions specifically prohibit the use of lasers in this way.
 * Also consider the Gyrojet. Replacing regular bullets with small rockets meant the projectiles needed to travel something like 60 feet before they actually do any damage. In addition a manufacturing defect made them wildly inaccurate, the four angled jets spin the projectile through the entire flight instead of just in the barrel so early tests were more accurate than rifles but in later runs one of the jets was partially blocked off by accident.
 * Um, the bullets hit 100 ft/s within a foot of leaving the barrel, and from there only go faster (hitting 1250 ft/s at 60 feet, or about 50% faster than the M1911 at point blank). It was also lighter, had a flatter trajectory (making it more accurate than conventional pistols, once the ammunition issues were sorted), produced no recoil, and virtually no noise either, at least at the launch end. Ammunition was a bugger though, expensive to manufacture and requiring high tolerances.
 * There was once a drill bit which drilled square holes (the cross-section was a Reuleaux triangle, a rounded triangle of constant diameter). The trouble with it was, it needed a template to be affixed to the drilling site and a special floating chuck to spin the bit. For most purposes, drilling a circular hole (or set of holes) and sawing/filing out the rest is a lot more practical.

Meta
"Yahtzee: ...the world's largest pie couldn't honestly be called a good pie because it's uneconomical and probably wouldn't fit in an oven."
 * The 11 Most Retarded Fictional Weapons.
 * In the words of Yahtzee:


 * This website, naturally. It may be cool to know pretty much everything about every piece of media out there, but good luck being able to concentrate on anything else like homework, work, a social life...