Chess computers have come a long way over the years. The latest models such as the DGT Centaur are now capable of beating all grandmasters. The Novag Diamond II may not be as strong but was way ahead of its time. Introduce in 1997, this chess computer has an estimated rating of 24020 USCF.
The Novag Diamond has a press sensory board and uses LEDs to show the moves. It is powered by a 32Mhz processor. The above video shows it in action.