LiveScience.com has a cool article looking at the history of computers.
Check out the Difference Engine (isn't that just the most awesome name?) designed in 1822 but not built until recently.
The greats are all there: ENIAC, the IBM 360, the Xerox PARC Alto, the Apple II.
In a parallel universe, they were joined by the Batcompter, HAL 9000, Colossus and the M-5 Multitronic Unit.