This year's Turing award for human-like Chat Bot announced on the BBC. [article ]
Boing Boing has already noted the Wired article pokerbots on bot's in on-line poker rooms.
I tried posing as a bot in an experiment and failed miserably. I hesitated too long on dumb postings and responded right away to relatively complex postings. The actual AI researcher tried to throw folks off the scent by asking how the random delay was working, but I couldn't stay in character very well. It took us quite a while to out the real bot because (a) it was pretty good and (b) it's personality was "lurker" so it responded rarely, and then only to specific kinds of things.