When my intro class reads Leiber's Can Animals and Machines Be Persons? I usually bring up many remarkable examples of machine intelligence. Today, I got a good one from a student. This little handheld novelty item plays 20 Questions, and is remarkably good at it, at least if you play fair. The first game I played, I was thinking of The Threepenny Opera, because I had just read a New York Times review of a production of it. The little ball guessed "A rock band." The second time I decided to go easier on the hunk of plastic, and thought of a computer. It guessed correctly.
I like this device for two reasons. First, it has to encode a lot of common sense in order to play 20 questions. The little ball has exactly the sort of knowledge people say is hard to capture.
More importantly, though, my father in law loves to play 20 questions and he always wants to be the guy who is thinking of something. I get tired of this game quickly--but now there is a machine to do it for me!
Update: I just played while thinking of "a father in law" and it guessed "a human being." Pretty good.
The machine must have some sort of explicitly designed ontology, a list of the sorts of things that exist and the properties they can have. I wonder if it makes any interesting metaphysical assumptions. Thomas might now something about this. He told me that what he did for a living (data modeling) was different than applied ontology, but it is still hard for me to see how.