This game uses AI to try and guess what you're thinking of in twenty questions or less.
"The artificial intelligence behind the game is a neural-network, similar to a human brain. A brain, or neural-network, is built from neurons connected by synaptic connections. A human brain has about one hundred trillion (100,000,000,000,000) synaptic connections. The 20Q.net online version has about ten million (10,000,000), and the pocket version has about two hundred and fifty thousand (250,000). The game uses the neural-network to choose the next question as well as deciding what to guess."