<Didn't Danny Hillis make a computer from TinkerToys <(TM) as part of his PhD thesis or something? I've been looking for the <schematics.... I haven't seen schematics, but there was a write-up of a TinkerToy computer which plays Tic Tac Toe in Scientific American a few years ago; sorry, I don't remember the year. I do remember the description being good enough to make me feel that I understood how the thing worked and, with a little enthusiasm and a bunch of TinkerToys, possibly replicate. Perhaps now that I have a big pile of K'NEX I should find the issue and give it a go. IIRC, the Tic Tac Toe machine is essentially a ROM lookup table. You encode the current state of the board on a part of the machine which slides up and down then hoist that part to the top. As the part falls, it compares the state of the board to the various entries in the ROM. Upon finding a match, it waves a flag indicating its move. Roger Ivie ivie(a)cc.usu.edu