Thanks (I think) to Tony Goodson & Dave Weinberger, for pointing 20Q out to me.
20Q is an online game of 20 questions that apparently starts off with no knowledge base, but learns from the answers you give it to guess what you are thinking!
Try it, I used fork, pen, matchstick, light... and it worked by asking an average of 22 questions.
Buggered if I know how it works, but it's impressive. And addictive (you have been warned!)
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