Super Mario Bros. Special occupies a strange place in Mario history. It's one of the few Mario games produced for a system other than Nintendo's own, licensed by Hudson Soft for the Japanese PC-8801 computer system. The system was fairly weak compared to an NES, so it didn't scroll; when Mario gets to the edge of the screen, it flips to the next. The game wasn't always designed with that in mind however, leading to a lot of blind jumps. You can play a hacked version of the original Super Mario Bros. designed to recreate this game using the patch found here. And here's a video playthrough of the whole game: World 1, World 2, World 3, World 4, World 5, World 6, World 7, World 8, Last level & ending. And here's a trap room in World 4.
Here are fan-translated Game Center CX (previously) Episodes on YouTube: #1: Atlantis No Nazo, #2: Challenger, #3: Ghosts 'N Goblins, #4: Konami Wai Wai World, #5: Metroid, #6: Solomon's Key, #7 & #8: Prince of Persia: Part 1 - Part 2, #9: Mega Man II, #10: Super Mario 3. Much more after the break.... [more inside]
Vs. Airman is kind of mind-blowing the first time you see it. It is not a PC or flash game, but a romhack that can run on a real NES. But which game is it a hack of? [more inside]
Take a game like Super Mario Bros. Introduce garbage data into the code, either through random Game Genie codes or a corruptor program. Try to play what results, while the laws of reality slowly go insane in the background, and upload the "best" results to YouTube. Can Mario make it to the princess when stomping a Goomba turns the air to water, when hitting a block ends the world, when the world is infinite length, if the ground can't support his weight, when touching a flagpole destroys his mind, when brought into being over an ocean immediately before a fatal heart attack, before the enemies turn into Bowser-halves, while the universe is freaking out around him? (hint: no)
Remember Super Mario Frustration? Kaizo Mario World is another of those super-hard Mario level hacks, this one of Super Mario World. Someone played through its first level 134 times, with save states, recording all his deaths, then digitally composited them into one trip through the level. The result was Many-Worlds Mario. (For those interested, here's a video of a tool-assisted perfect run of much of the game. Here's the rest. Here's some more.)