Genius Programming

The opposite of Idiot Programming. Your disk space, processor speed, and RAM are scarcely limiting factors to somebody who knows what they're doing. You'll find smart developers can take your hardware way Up to Eleven to give it capabilities not seen in typical software on more powerful machines for 5 or 10 years.

Demoscene
"Person: FIND A BLOCK WHICH IS TALLER THAN THE ONE YOU ARE HOLDING AND PUT IT INTO THE BOX.
 * .kkrieger by Farbrausch is a game with Doom 3-tier graphics… that could fit on a standard floppy disk fourteen times.
 * By the same crew, fr-08: .the .product, a demo with impressive graphics (for the time) in sixty-four kilobytes.
 * These guys have a lot more stuff, available here.
 * Due to their experience with procedural generation, many demoscene programmers were hired to work on Spore.
 * This troper was proud to be responsible for a slashdot poll of The greatest hacks which put The Future Crew's "Second Reality" as one of the top candidates. Nearly twenty years later it's still mindblowing how much it was able to accomplish with so little.
 * SHRDLU is an AI/text parser written by Terry Winograd (MIT Artificial Intelligence Laboratory) from 1960-1971 that can manipulate blocks and pyramids according to commands entered by the user, and also answer questions about them. In plain English . This is an excerpt from the demo:

Computer: BY "IT", I ASSUME YOU MEAN THE BLOCK WHICH IS TALLER THAN THE ONE I AM HOLDING.

Computer: OK. (does it)

Person: WHAT DOES THE BOX CONTAIN?

Computer: THE BLUE PYRAMID AND THE BLUE BLOCK.

Person: WHAT IS THE PYRAMID SUPPORTED BY?

Computer: THE BOX.

Person: HOW MANY BLOCKS ARE NOT IN THE BOX?

Computer: FOUR OF THEM.

Person: IS AT LEAST ONE OF THEM NARROWER THAN THE ONE WHICH I TOLD YOU TO PICK UP?

Computer: YES, THE RED CUBE.

Person: IS IT SUPPORTED?

Computer: YES, BY THE TABLE."


 * State Of The Art by Spaceballs. The YouTube video really doesn't do justice to how impressive it is to watch this thing running on a 16 bit machine with 1 megabyte of RAM, a 7 MHz processor and an 880K floppy drive for storage. The fluidity is all the more impressive when you remember that the demo is constantly loading new data in from the floppy drive while displaying all that animation.
 * Tint (possibly NSFW due to a second or two of boobies) by The Black Lotus. Needs rather meatier hardware to run than the aforementioned State Of The Art, but the real-time lensing and fluid effects near the end will blow your mind. Also, Crowning Music of Awesome helps a lot.
 * The 8088 Corruption, a demo that runs "video" at 60 frames per second and impressive digital audio, on an old IBM PC, using the Intel 8088 flavor of processor. For those that don't know their computer history, the 8088 is a 16-bit processor, but it's crippled to an 8-bit data bus.

Video Games

 * Recca is a fast-paced Bullet Hell shooter with awesome graphics, creative bosses, homing weapons and techno music. Even with more than 20+ enemies and bullets on the screen, there is usually little to no slowdown. One must wonder how Naxat Soft managed to code something like this for the NES.
 * Tales of Phantasia may not be ridiculously small in size, but this game pushed the capability of the SNES to its limit. For example, Scenery Porn, which is deemed ALMOST impossible (at the time). Then the programmer try to MESS with the sound as well by...insert whole theme song with voice into the opening! Now that's genius. Every Tales game since has a theme song, but it's less impressive when better sound hardware is involved (though many of these have the lyrics removed up to Tales of Vesperia). Almost every concept from this game was then (by the same people after they quit at Wolf Team to form tri-Ace after their old publisher, Namco, interfered with their previous work) imported to Star Ocean.
 * The Elder Scrolls II: Daggerfall has a world the size of 62,394 square miles which takes two weeks in real time to walk across, over 500,000 NPCs in 15,000 locations. It's about 148 MB and made in 1996.
 * To be fair, most of it is randomly generated. With the press of a button they could have made a hundred thousand more.
 * Dwarf Fortress uses a complex algorithm to generate a realistic world every time (complete with a detailed history of every person and place that ever existed there), keeps track of injuries to specific body parts down to individual fingers and toes and even further down to tissue layers, provides an extremely detailed fortress simulator, and even has a script which simulates hydrostatic water pressure… Yet the whole thing is about five megabytes. On top of that, all the programming is done by one guy. Holy crap.
 * Note, however, that the program is still in the alpha stages of development, so the current versions are all debugging builds. What this means in practical terms, aside from numerous Good Bad Bugs, is that the program consumes utterly preposterous amounts of memory and slows even the mightiest CPUs to the speed of molasses. This is perfectly normal for debug builds of a program, so once it's relatively feature-complete, the lone Mad Genius writing it says he'll begin performance tuning.
 * It will be feature-complete when he's dead.
 * The original Elite: The game features a Wide Open Sandbox of eight galaxies of 256 stars each, each one with its own unique description and characteristics as well as numerous ship designs. It's the game which launched the entire genre of Space Trading Sims. It was quite literally years ahead of its time. And the whole thing fits on ~20 kilobytes of disk space.
 * That's because all content (planet names, their coordinates, commodity prices, etc) in the game was procedurally generated and, basically, boils down to the single 8-bit seed number and a couple of rules checking that you won't get planets named “Fuck” or “Arse.”
 * The sequel, Frontier, isn't too shabby either. The PC version has over 20 textured 3D models and enough star systems to fill the entire Milky Way, yet fits on a single 1.44MB floppy.
 * Bonus points for being one of the first commercially released truly 3D games.
 * Rollercoaster Tycoon kept stats on every visitor, in addition to controlling all their AIs simultaneously, all while animating all of it and allowing the user to interact with it. And all this could run on a PC made in the early '90s, without lag. The secret is that the system was programmed in raw Assembler, only relying on more high level code for graphical stuff.
 * The same secret allowed ZSNES to run games at full speed well before its competition, but it's showing its age now as one of the few actively maintained programs that can't be compiled as 64-bit, due to the incompatibility of 32-bit and 64-bit assembler and the changed calling conventions for C code(64-bit mode added extra registers, which made it possible to use some to pass arguments). The devs currently have no plans to address this.
 * The performance of RCT 1 & 2 is even more impressive compared to the third iteration, which had widespread graphics card compatibility problems and brought many contemporaneous systems to their knees. Hell, many 2009 PCs struggle when everything is maxed.
 * Escape From the Mindmaster: Faux First Person 3D with smooth movement from square to square on the Atari 2600.
 * Exile-no, not that Exile-was a Metroidvania-ish title that managed to feature surprisingly realistic 2D physics for objects and even windy areas, as well as a living ecosystem for what was originally a BBC Micro title released in 1988. With a RAM expansion, the game could even play voice samples on that same hardware!
 * Irisu Syndrome. In at least one of the endings,  It's nothing miraculous, but it's a pretty cool Interface Screw by PC game standards, especially for a freeware indie game.
 * The game also puts text files into the game folder as you play the game, either of character profiles or accounts of what are likely backstory events, and swaps out a picture in the game folder with other versions of it as you go along. Too bad there isn't a Fan Translation available. And now that there's a Fan Translation available, you get to read them for important backstory.
 * Below The Root for the Commodore 64 was one of the earliest games where you could pick the gender, race, and age of your avatar - with stats altered accordingly, and with hidden stats that fit the race in question. Erdlings got knocked for a loop by Wissenberries, wheras Kindar had a tolerance, Kindar took a hit to their spirit stats by eating meat. It was, very possibly, the first game to be considered an authorized, canonical sequel to material written for another medium. Yes, the distant ancestor of The Force Unleashed is possibly a 1984 side-scroller where killing anyone makes the game Unwinnable.
 * Starcraft II is not merely an RTS, it is a General Purpose Game Engine. Blizzard approves
 * Minecraft is a bit like Dwarf Fortress with a first-person viewpoint minus all the complexity. Most impressively, it can support randomly-generated worlds eight times the surface of the planet Earth in size.
 * The programming team behind Spyro: The Year of the Dragon had a unique insight into preventing piracy: You can't. However, it doesn't matter, because 30-50% of the sales of a game are made in the first two months. So, with the goal of slowing down pirates as much as possible, the developers started by designing "crack protection," distinct from the normal copy protection (which detects whether the game is run on a DVD-R). The crack protection they came up with relies on a checksumming system that's ingenious and more than slightly twisted; by interleaving, overlapping, and combining multiple checksums over a block of data, it's virtually impossible to make them all add up if even one bit is changed, but because not every checksum goes over all of the data (and because CRC has a few exploitable weaknesses), the checksums being compared to can be a part of the data being checksummed. This, combined with tons of other traps designed to make life hell for pirates, meant that it took over two months for a working crack to finally be released (at a time when "Wow, that hasn't been cracked yet?" meant something like four days), and only then because the developers held back to avoid Loads and Loads of Loading.
 * Fast inverse square root, also known as InvSqrt, 0x5f3759df, and "What the fuck?" after its implementation in the Quake III Arena source code (and infamous comment). The algorithm, which uses a novel first approximation of Newton's Method to get an almost perfect second approximation, runs roughly four times faster than traditional implementations, and still faster than other "optimized" algorithms of the time.
 * Space Invaders for the Atari 2600 seems simple enough, but the Atari 2600 is only capable of displaying two player sprites, two rectangular shot sprites (one per player), and a rectangular ball sprite simultaneously. Atari 2600 Space Invaders can have up to 39 player objects and four shots on the screen at once, with no extra RAM or other special chips on the cartridge. It was doing things that the console literally shouldn't have been able to do.
 * Given that the Atari 2600 is optimized for simple, symmetrical games like Pong and Combat, MOST of the games on the Atari 2600 represent Genius Programming.
 * Before Star Control there was Starflight and its sequel, Starflight II. Hundreds of planets, all unique, dozens of alien races, an epic backstory, and a quest to Save The Galaxy. And it all fit on a single 720K floppy disk, or two 360K floppies.
 * Earthworm Jim 2 manages to pull off voices in the theme song and rock music that's not midi, even in the SNES and Sega Genesis versions.
 * ROM Hacks in general, especially when they go beyond what you'd think the game engine or even the system was capable of, for example:
 * Brutal Mario/Super Kitiku World and its massive use custom assembly to do things Mario World wouldn't do otherwise.
 * Rock Man 4 Minus Infinity has done some rather crazy things, which includes not only a lot of weapon changes, but a few on screen effects that are on par, if not better than the effects in Battletoads.
 * Give or take, any of the really well done Mega Man 2 hacks.
 * Rockman 5 Air Sliding featured its unique titular gameplay mechanic, alongside some interesting level and weapon changes (including an improved Gravity Hold and making Stone Man's level orient itself to the left).
 * Super Mario Oddysey and other Mario hacks using the MSU 1 patch. Why is this? Because with a custom patch, they've managed to get MP 3 quality music working on the SNES, as heard/seen here
 * From the dawn of computing, the legendary Mel Kaye's Blackjack program for Royal McBee LGP-30 and RPC-4000 machines. Not only was he able to squeeze the whole program into just the 4096 words of drum memory, but he was one of the first Real Programmers who basically pioneered most of the Heavy Wizardry techniques discussed above, including using code as constants, optimizing the code by hand to eliminate even smallest wait states and delay loops, and using self-modifying code to do so. Ed Nather, the author of the story above, when asked to rewrite it spent a whole month just trying to understand Mel's code, and upon finding an endless cycle without a check, which just happened to use an overflow error to modify the last command of it into a different jump and exit the loop, he gave up out of respect.
 * When Al Lowe made Leisure Suit Larry 3: Passionate Patti in Pursuit of the Pulsating Pectorals, he found a way to eliminate the loading time between room changes (which must have been pretty long on machines of the time) in the bamboo maze. He did this by using the same background for every room of the maze. The background had exits in every possible direction. The exits that weren’t supposed to be open in a particular room were covered up with overlays. To hide the fact that it was always the same background, he mirrored it, along with the overlays, every time you left the room. This also saved a lot of memory and disk space.
 * Scribblenauts: game that boasts a dictionary of few dozens of thousands words, with each word having its own graphical representation, animations and interaction patterns (like elephants being afraid of mice and so on) was crammed into a 32 megabyte Nintendo DS cartridge. Even more impressive in Super Scribblenauts with added adjectives (everything still fits into a 32 MB ROM chip).
 * The Pokémon Stadium battle code was ported to the Nintendo 64 by the then acting president of HAL Labs within a week without any documentation available. Also, when he was a kid he used to perform disassembly on the programs for his home computer by writing down the memory dumps by hand (since there were no printers available). He (Satoru Iwata) is now the global president of Nintendo.
 * As a further testament to Iwata's abilities: during the development of Earthbound, it somehow devolved into a veritable coding mess which nearly killed the project out of sheer unworkability. Then Iwata was brought in, decided the original coding was unsalvageable, and single-handedly reprogrammed the entire game from scratch in a very short amount of time, saving the game from what seemed like certain doom.
 * Bear in mind though, Clyde "Tomato" Mandelin found out that the entire game is basically one giant, still incredibly messy scripting language, guaranteed to explode the heads of anyone who tries to alter it. Iwata isn't just a genius programmer, he's hardcore.
 * Iwata later personally compressed Pokémon Gold and Silver after the programmers at Game Freak used up all of the space on the cartridge. He left so much space, Game Freak put in a second quest set in Kanto, the setting for Pokémon Red and Blue, with all but two of the locations intact and largely unchanged.
 * Naughty Dog loves to show off their technical prowess. The Playstation 3 is almost infamous for requiring data installs, as searching for and loading information off a high-capacity Blu-Ray disc would result in extremely long load times...or so people thought. Uncharted 2 required absolutely no installation, and the only loading time you would see is when the game starts up (about 10 seconds), and when you start or continue a game (again, about 10 seconds). The rest of the game loads seamlessly, not stopping for anything, including area transitions, from start to finish.
 * The iconic scene in the same game, the train sequence, is also a marvel of technical engineering. In addition to adjusting the physics to account for the fact that Drake's on a train, the entire sequence, from the start in the jungles to the end in the snowy mountains, has no repeated environments. Every single view and vista is unique, and waiting long enough for, say, the point where it's curving around a lake or mountain, will eventually give you alternate views of the location as your position shifts. And to top it all off, you can see the train curving ahead of you in the distance: you can reach all of those cars, and eventually will.
 * Mickey Mania pulled off some impressive perspective tricks in a number of its levels, with stages such as a Nebulus-style rotating tower and a head-on moose chase. Not so much of a big deal on the SNES, with its GPU support for background perspective in Mode 7. It is, however, a big deal on the Sega Genesis, where all of these effects had to be emulated in software...
 * Jett Rocket set the standard for what could be done with the Wii Ware's 44 megabyte limit. To most developers, this is a cripplingly small amount, and they deem it unreasonable and unworkable. Shin'en Multimedia created a full-length 3-D platformer on it that looks and plays like a retail game.

Other Software

 * ReactOS: the project aims to create an open-source Windows-compatible operating system from scratch. After 12 years of development, it has some basic compatibility with Windows. You may not be able to run the latest games on it, but you can check your email and browse All The Tropes.
 * On that note, Wine. It's a project that attempts to recreate the full Windows API on Unix-based systems. It's not an emulator, either (it's actually part of the recursive acronym: Wine Is Not an Emulator,) but is actually a piecemeal reverse-engineering of Windows one library at a time, which makes Windows-only applications run just fine on Unix and other OSs. This includes very modern games like Team Fortress 2, which are fully playable this way.
 * Also note that Wine and ReactOS are a sister projects and have a shared codebase. Or, more correctly, Wine is a Windows-compatible userland to run application software atop compatible kernels, while ReactOS developers concentrate on a Windows-compatible backend side, that is, kernel and driver support.
 * Pretty-much any Emulator qualifies. Especially ones which emulate hardware for which there is little or no official information available, requiring the use of reverse engineering.
 * SNES Advance and Snezziboy are particularly impressive - fully playable SNES emulators squeezed into a Game Boy Advance.
 * A lot of programs in an esoteric language count, just because of how weird the languages are. Take, for example, this.
 * The video editing program Sony Vegas is a bit of a Mind Screw until you get used to it, but once you do it is a dream. (Or the results it allows are; it can be laggy, but it's all worth it.)
 * High Efficiency Advanced Audio coding w/ Parametric Stereo. A pretty general rule of thumb is that it gives the same as MP 3 quality at one forth of the size (24kbit HE-AAC sounds as good as 96kbit MP 3). Discovering it has been known to lead to at least one joygasm.
 * Preceded by mp3PRO, which uses the same Spectral Bandwidth Replication algorithm to shrink the file size to half.
 * jQuery is a JavaScript library that is used in a surprisingly high proportion of the most visited web sites. That is because it allows you to do a number of things that are (currently) too high-level for plain old HTML, JavaScript and CSS to handle out of box, such as AJAX (increased online interaction without refreshing the page you're on), manipulation of HTML elements (that is, inserting or tearing out parts of the web page at will), and basic animations (such as fade-ins and fade-outs). In other words, it provides just about all the functionality that really sets apart modern web pages from the static web pages of yesteryear (where yesteryear is approximately any year prior to 2005). It is also designed to be as unobtrusive to other code as possible, only uses confusing trick code where unavoidable, and still only clocks in at under 100 kilobytes.
 * Microsoft Excel. While mostly known for being a boring spreadsheet program, it is actually very versatile. If you know what you're doing you can turn it into a rendering program or even a game engine with no real modification of the software.

Other uses

 * The CGI in Tron. Procedural texturing was invented for this movie. Even the one-off supercomputer used at the time didn't have enough memory to be able to use raster textures, so the only way to get any detail was by evaluating functions on a per-pixel basis.
 * Pinball. That is all.
 * Here's an interview with pinball programmer Dwight Sullivan, in which he describes how small the pinball software was at the time. Notable programmer Larry DeMar (the co-creator of Defender and Robotron: 2084) invented automatic replay adjustment (with Steve Ritchie; which automatically adjusts the replay score based on the players' performances on location) and software compensation for broken playfield switches/features, both of which were introduced in 1986's High Speed.
 * Noteworthy mention goes to 1992's The Addams Family, which had an auto-flipper (called "Thing Flips") that actually did hit the Swamp scoop target, most of the time. When it doesn't hit the Swamp scoop, then the software auto-calibrates the flipper until it hits the Swamp. This also happens if the pinball machine is moved to another location. Not surprisingly, Larry DeMar was the co-programmer for The Addams Family.
 * DeMar also did the programming for 1990's FunHouse, which featured "Pin-Mation", in which Rudy's (the talking doll head) eyes and mouth move in real-time, depending on where the ball hits the target.
 * TicketMaster managed to conquer their market by using such tightly written code it could run on 1/10th the space of its original competitors and still process the same amount of requests at the same speed.
 * Apollo Guidance Computer software implemented a (cooperative) multitasking operating system plus all the software to run on it in 36,864 16 bit words of ROM and 2048 16 bit words of RAM (or in modern units, 73,728 bytes and 4096 bytes, respectively). And this was software that had to be extremely reliable and fault-tolerant because human lives depended on it. Apollo 11 demonstrated the benefits of the fault tolerant design when the guidance computer was given slightly more work than it was capable of coping with during the landing. Instead of curling up and dying, it issued an alarm, discarded jobs that were considered low priority and continued running the high priority tasks. This bit of design saved the mission.
 * When you consider that a lunar landing abort would have been the most complicated manuver ever attempted by NASA (possibly to current day) this feature likely saved lives.
 * Linksys's WRT54G (and its spiritual successor, the WRT54GL, ) wireless router is one of the most hackable routers, because its firmware was based on Linux. After Linksys released the firmware source code under the GPL, software developers began developing customized versions of the WRT54G firmware, the most well-known being DD-WRT and Tomato. Not only are they considered to be more reliable and better performing than Linksys's stock firmware, they would add advanced features that are only available in commercial-grade routers.