The Antikythera Mechanism, sometimes called the first analog computer, was recovered more than a century ago in the wreckage of a ship that sank off the tiny island of Antikythera, north of Crete. Earlier research showed that the device was probably built between 140 and 100 B.C.
Only now, applying high-resolution imaging systems and three-dimensional X-ray tomography, have experts been able to decipher inscriptions and reconstruct functions of the bronze gears on the mechanism. The latest research has revealed details of dials on the instrument’s back side, including the names of all 12 months of an ancient calendar.
Neat because it's actual data.