Big on Digg yesterday was a face mutations site called Mutating Pictures that would let you rate how much a randomly thrown together pile of geometric objects looked like a human face. Voting up a picture would in turn create more "offspring," or similar variants of the chosen picture, while simultaneously "killing off" the lower ranked faces. The result is a user-controlled evolutionary system at a very basic level.
Today, almost ironically, we've got a mutation of the site called Face Maker that attempts to solve the same problem using an either-or model. Instead of voting on the hot-or-not sliding scale of one to ten, you pick which one looks "more" human. Like Mutating Faces, Face Maker will kill off the lesser choice, and spawn more recruits from your choice.
The cool thing about both projects (besides the unintentionally awesome Rorschach-inkblot-test-meets-fractals look and feel), is that you can view the progress in real time. You can see before and after pictures of facial progress, and even trace it back by generation. If faces aren't your thing, there's a also freshly launched "animal" section, which gives you the chance to figure out if the random shapes look more like a duck, or a teddy bear. Creepy.