Pac Man

Screengrab: Pushing Arcade Games to the Limit

Any player who reaches level 255 on the arcade classic game Pac Man, the game will glitch out. When it tries to load level 256 the game will go on over load and the fruits, ghosts, cheats and numbers will pop up on one half of the screen. It is still possible to beat with a perfect score but it is very hard.

http://www.wired.com/magazine/2010/08/pl_killscreens/