Here a few Games and Toys for your surfing pleasure.
Eliza – not so much a game as a strange kind of AI analyst. The code is very simple, but people have been known to play for hours.
The God Program – Also no a game, but a running script of the output of a God program.
Dick Eyes – A toy where Philip K. Dick, a master of Science Fiction, is brought back to life and his eyes wander around the room.
I have more kicking around, if I could only find them.