I remember Microsoft used to have this AI game for the .NET framework which allowed you to program a species and this species could be introduced to an "ecosystem" full of species that other people had programmed and they could interact with each other, etc.

I can't remember what it was called, but I remembered thinking it was a pretty good idea.

Are there any other similiar sites like that, which allows you to design some sort of AI engine and pit it against other programmer's creations? It could be an ecosystem type thing, or it could be a card or board game.