Weapon for Intimidation

The designer of the gun had clearly not been instructed to beat around the bush. "Make it evil," he'd been told. "Make it totally clear that this gun has a right end and a wrong end. Make it totally clear to anyone standing at the wrong end that things are going badly for them. If that means sticking all sorts of spikes and prongs and blackened bits all over it then so be it. This is not a gun for hanging over the fireplace or sticking in the umbrella stand, it is a gun for going out and making people miserable with."

—The Restaurant at the End of the Universe

They say that the best weapon is one you never have to fire. I respectfully disagree! I prefer the weapon you only have to fire once.

—Tony Stark, Iron Man

Not everyone who carries a weapon actually uses it. Sometimes it's best to have something to make you look intimidating, be it a large staff or a gun. It might actually be completely useless (such as an unloaded gun or even a toy gun). Other times it's just not needed all that much, but when you need it, it'll get the job done.

May lead to an unfortunate demise through the Shoot Him! He Has a Wallet! trope.

Subtrope of Useless Accessory. The Sword of Damocles is an upscaled version of this trope; a weapon so fearsome it brings nations or worlds to their knees in fear of it. If you don't even have a fake weapon, but wish to achieve the same effect, that's a Brandishment Bluff.

Examples of Weapon for Intimidation include:

Anime and Manga

In Sand Land, when Rao is asked why he didn't use his gun in a fight, he answers that bullets are expensive (especially in a Desert World) and pointing his gun is enough to scare most would-be bandits.

Comic Books

In 2000 AD‍'‍s D.R. & Quinch, Pulger once carved a (fake) phaser rifle out of a bar of soap as part of a prison escape attempt when traveling the tunnels burrowed out by a species known only as the "Snufflegruffs". When one of them shows up, Pulger makes his best attempt at this with carved-out bar of soap.
- And then he does it yet again with what's left of the soap gun in the following installment.
In Queen & Country, Chace is being hunted by a Russian mob hit squad. The minders aren't permitted to use guns domestically, so they buy bb guns and paint them to look real in the hopes that this will frighten away the killers. When that doesn't work, they have to pistol whip the guys to death with their toy guns.

Film

Philip Marlowe in Murder My Sweet carries a revolver but states that he rarely needs it.

"That's just part of my clothes. I hardly ever shoot anybody with it."

In Lock, Stock and Two Smoking Barrels, Soap states that people are more intimidated by knives than guns because they're quiet, and thus can be used without attracting the police. He concludes, "Guns for show, knives for a pro."
Snatch has a few of these:
- Vince buys a gigantic shotgun to "raise pulses" when he robs a bookie joint. He actually uses it to blow a hole in a wall, then gets it turned against him.
- Later, Sol gets two starter pistols loaded with blanks as intimidation weapons against Bullet-Tooth Tony, who notices that they've got "Replica" written right on them.
- Tommy's gigantic revolver is bought for self-defense, but it actually doesn't work. He still keeps it around, and uses it as an intimidation weapon against Brick Top's dragon and a bunch of Mooks. Doubles as an unexpected Crowning Moment of Awesome for Tommy, who is absolutely convincing while threatening the mooks.
Inside Man has the bank robbers armed with AK-47s that they never fire and Clive Owen has a Hand Cannon that he uses for intimidation. The guns are all fake.
Woody Allen's Take the Money and Run. Virgil tries to escape from prison by threatening the guards with a fake gun carved out of soap. Then it starts to rain...
In Raising Arizona, HI always robs stores with an unloaded gun, which is what helps him get out of prison so quickly to stick up another joint.
Fight Club has a scene where Tyler Durden takes a store clerk out the back of the store and holds a gun to the back of his head, scaring the wits out of him and forcing him to go and follow his old dreams of being a veterinarian. At the end of the scene, the protagonist (who was with them) opens the chamber of the gun and sees there are no bullets inside.
In The Gumball Rally, hot-blooded Franco pulls a gun from a paper bag and threatens another driver with it. It turns out it's a squirt gun, and the whole thing was a gag.

Literature

Dally's revolver in The Outsiders. It's not actually loaded, and he states that he uses it to scare people and that's all. This comes back to bite him when he raises the unloaded gun at the police after Johnny dies to get a Suicide by Cop.
In Farmer Giles of Ham by J. R. R. Tolkien, Farmer Giles's blunderbuss is this ... until he happens to fall over when meeting a giant.
Discworld:
- Evoked in The Fifth Elephant: Vimes is particularly distrustful of Skimmer's spring crossbow (described as similar to a derringer), which he says is not a weapon, but a tool for killing people. To Skimmer's puzzled "Uh, yeah, it's a weapon," Vimes responds that weapons are for displaying, so attackers know what they're heading into (like dwarves and their ubiquitous battle-axe). The spring crossbow, on the other hand, is for killing people who aren't expecting it.
- Also invoked in Monstrous Regiment where vampire Maladict carries a sword to keep people from attacking him. He doesn't know how to use it, of course, as his vampiric abilities ensure he doesn't need to, but "sword" proves a better shorthand for "not someone you should attack."
- And then of course, there's Detritus's crossbow, the Piecemaker, which is generally used as a threat, as opposed to actually being fired.
In Shards of Honor, Aral Vorkosigan says that this is the reason he prefers nerve disruptors or plasma arcs to stunners—he's seen people carrying stunners get ganged up on and killed, but nobody would have tried that if there was a risk of getting killed (or worse; remember Ensign Dubauer). Roughly thirty-two years later, Aral's son Miles gets told that this is why a rescue party (or a tactical strike-force committing a jailbreak; perspective's a bitch) was equipped with something stronger. He says that he recognizes the argument, but points out that the problem is, what if you actually have to fire the stronger weapons?

Miles: "So, after we shot up the police station and set the habitat on fire, what did we do for an encore?"

Near the beginning of Snow Crash, the protagonist decides to rely on his swords, rather than the toy-looking (but deadly) pistol he's been issued by his employer, to defend himself from muggers—because he's much less likely to have to use the swords.
E.C. Tubb's Earl Dumarest disapproved of this notion: he told one woman he'd rescued from thugs that when she drew her laser against them she should've started shooting at once. She asked, "Kill without warning?" and he replied, "Why warn if you intend to kill? Why draw a weapon if you don't intend to use it?" The narration notes that "Like a tamed dog she had bared her teeth hoping the sight would protect her, unwilling and unable to do more. A pathetic defense and useless against the predators she had met."
Early in Gordon R. Dickson's The Outposter, Ulla Showell thinks that having a small gun strapped to her wrist under her sleeve is being sufficiently armed. She doesn't want to listen to the regulations that say she has to wear a more visible gun, as part of rubbing in to the unwilling "colonists" that they must obey.

Live-Action TV

The Jaffa staff weapon in Stargate SG-1 is explicitly described as this: their primary purpose is to intimidate the low-tech slave populations and fight equally armed warriors of rival Goa'uld. In the hands of a trained Jaffa warrior, as Teal'c repeatedly demonstrates, staffs are lethal weapons both ranged and melee. Colonel O'Neill calls them out as weapons of terror and intimidation when demonstrating the efficiency of the team's P90 to a group of rebel Jaffa.
In an episode of Red Dwarf, the crew are creeping aboard a badly-damaged simulant ship, heavily armed with bazookoids, and feeling somewhat confident. Then Lister admits that the superstructure of the ship is so unstable that even a loud noise could cause a shipquake, so the bazookoids are for psychological use only. Cue Death Glare from the Cat.
- Before it's over, one shot is fired while aboard the ship ( actually, by the bad guys in a Taking You with Me moment.) This results in the ship going kaboom not long after the Boys from the Dwarf get clear.
In the first episode of Sherlock, the culprit threatens the eponymous detective with a gun. Before long, Sherlock has reason to call his bluff. It's a novelty lighter.
On one episode of Frasier, Niles needs to get Maris a gun for protection. After not being able to procure one, he buys a starter's pistol since having any kind of gun would make her feel safe.
In Have Gun — Will Travel, Paladin will often use his gun as a deterrent, either simply pulling it out or shooting an object to scare his enemy into backing down.

Tabletop Games

Intimidation value is certainly part of the mystique of BattleTech's BattleMechs, although this doesn't keep them from also being quite functional war machines. And then you get things like the Atlas, designed specifically to be "as powerful as possible, as impenetrable as possible, and as ugly and foreboding as conceivable, so that fear itself will be our ally". The machine isn't actually unbeatable in the game, being primarily a slow short-range fighter with somewhat limited ammunition stores; but it's still one of the heaviest 'Mechs ever built and a tough nut to crack, and you definitely don't want to be caught in front of it if it ever does manage to close the distance...and whenever one shows up on the field in the associated fiction, even other MechWarriors generally take notice, as it's armor and short-range damage potential are one of the highest possible with 3025-era technology.
- Similarly, fluff-wise anyway, the Titans from Warhammer 40,000 were not only designed to be humungous, walking weapons platforms, their mere presence was often enough to rout entire opposing armies. The largest ones, the Imperator class, are so big that someone jokingly "fielded" one in a tabletop game by making a cardboard costume and standing on the table over the roughly 1" models and kicking them all over. That said, Imperators have enough firepower to level cities as collateral damage, and even the smaller Warhounds and their ilk will trash a decently sized force. The intimidation comes from knowing that the fourty-to-two-hundred-foot death machines are every bit as deadly as they look.
GURPS Goblins actually provides game mechanics for this by giving every weapon a Menace attribute. A weapon's Menace is not necessarily tied to its effectiveness; a schoolmaster's cane may not be a very strong weapon, but it has a high Menace due to the painful memories seeing one can call up.

Video Games

In Metal Gear Solid 2: Sons of Liberty there are three weapons (a grenade launcher, a missile launcher and a guided missile launcher) which aren't particularly useful for general combat, but can easily scare almost any enemies into dropping items.
Kyle Katarn in Jedi Academy: "Remember, your lightsaber is an invaluable tool. Even when inactive, it can defuse a potentially hostile situation. Trust me on that." Of course, in the actual gameplay...
Liberal Crime Squad: You can try to intimidate or kidnap people, and it works better with a weapon. Even if you don't have the skill.
Sam in Sam and Max Freelance Police The Devil's Playhouse, when you try to use the gun on anything you are not supposed to, Sam states that "I don't need to shoot anybody, it's enough they know I have a gun."
I Am Alive has your gun be used in this way as you start with no bullets and what bullets you do find are few and far between.

Web Comics

Schlock's plasma cannon in Schlock Mercenary is quite dangerous but its ominous hum is the most important feature. So much so that he rejected a better gun because it was small and didn't hum.

Real Life

This was one of the purposes of swords for eighteenth and nineteenth century officers; it helped herd fugitives back into the battle line. As with skilled hands a sword can be as lethal or non-lethal as the bearer wishes it to be, that makes it useful.
Most US Policemen carry a gun as a matter of course but never use it in combat. However, if they are in a situation where they might need to intimidate someone, they are more likely to simply break out a taser or pepper spray, which are much more reliable than intimidation and reduce the chance of injury to both the officer and suspect.
Averted in the case of concealed weapons permit holders. No one's ever supposed to know you're packing until you need to actually use it on an assailant, and brandishing a weapon to threaten can get you in serious trouble, with or without a permit.
The atomic bomb counts. After Little Boy and Fat Man got used in World War II, no one dared to use them ever again in any conflict. Considering its world-ending potential, its only effective use is as a deterrent (both from conventional invasions as well as other countries with nukes). The weapon you only have to fire twice.
Tthe Gatling gun was designed to reduce casualties by decreasing the size of armies and intimidating armies into preemptive surrender. Unfortunately, it didn't have the intended effect.
Security experts often say that a pump-action shotgun is the way to go for home defense, with its loud and unmistakable "Shk-SHK!" sound of the shell being cocked. Plus, in the unfortunate event that an intruder calls your bluff, your typical 12-gauge's low muzzle velocity means that a shotgun is less likely to over-penetrate and harm innocent parties that you would still be legally liable for harming.
- The trope is actually invoked in some US states, where the sound of a pump action shotgun being cocked legally qualifies as sufficient warning to leave the owner's property.
Because guns are banned in the UK with a few exceptions, most gun crime is done either with an air rifle (which won't be killing anybody) or with a gun with no ammunition at all (as while guns are frequently smuggled in, bullets are apparently harder to obtain). Nevertheless, when a criminal's gun pointed at unarmed people, that's no time to take chances on whether or not they can actually kill someone.
The M1 Carbine is loved among veterans who carried it as backup, but never had to use it, due to its low weight and easy handling that ensured it did not interfere with their support roles (like artillery crews and transport operation) like a full rifle would. Those that actually used it (Except possibly the ones who got the late war night vision scope) regularly derided its unreliability and the terrible power of .30 Carbine.