MENACE is a learning machine made out of 304 matchboxes, which plays noughts and crosses - and, over time, actually learns to play it better. Constructed for a lecture at Playful 2009, it is an instantiation of a thought experiment by AI pioneer Donal Michie, the Matchbox Educable Noughts And Crosses Engine.
→ More information, together with notes and slides from the Playful talk
The talk and the machine were featured on BoingBoing, Gizmodo, MAKE Magazine and numerous other online sources. It also appeared in the print edition of Dutch newspaper NCR Next (cutting).