"No, I want to play global thermonuclear war."
The original ELIZA program (state of the art natural language AI in 1966!):
http://chayden.net/chayden/eliza/Eliza.shtml
There are a bunch of web-based AI and expert systems listed here:
http://uk.dir.yahoo.com/Recreation/G..._Intelligence/
This one is pretty amusing -
http://www.zabaware.com/webhal/uncen.html
:smoker2: