A game based on the XKCD comic of the same name. When you jump, gravity slows you down to zero vertical velocity, but doesn't pull you down (until you hit something). The longer you hold SPACE, the higher you jump. If you get stuck above the world, you'll have to restart or wait before you can return to your starting position. Jump was created for the XKCD Game Jam.
The comic below, created by Randall Munroe, is available under CC-BY-NC 2.5
Project available under GPLv3, but not the comic (obviously).