The Antikythera Machine
New Scientist (the liveliest of the journals) and The Guardian posted this video of the rebuilt "Antikythera Mechanism", a machine found in a Greek shipwreck some 2,000 years old.
There's an argument on Wired as to whether it's a computer or a clock. Since it predicts points in time-- like calculating upcoming dates for the Olympics-- I say it's a computer. (The x-ray shows the inner workings of the original device.) I've been interested in ancient technology all my life-- Hero's steam engine, the citric juice battery used by the Egyptians for electroplating-- and seeing this mystery restored and deciphered is a wondrous thing.