The following chess computers are spares and can be bought or swapped (click to see more details):

Chess Champion Mark 1
€ 10   € 7.50
One of the oldest

Excalibur Talking Touch Chess
  € 40  € 35
handheld, strong program

Chess Challenger 3
  € 45
First correctly-playing chess computer, 1977 (no chessmen)

Voice Sensory Chess Challenger
   € 70
Sensory computer with voice, (1980, wooden chessmen)

Novag Sapphire II
  € 45  € 40
Very strong play, second-hand (1997)

Scisys Travel Mate II
     € 30  € 25
travel computer, 1986

425XLight
     € 25  € 20
transparent board & chessmen, pretty light effects

LJ-691
  € 15  € 10
pocket computer, touch screen, backlight

SC2
     € 50  € 40  € 35
East-German computer, wooden chessmen, rare (1981)

Super 1680L
  € 30  € 25
very suitable for occasional players

Tandy 1650 Fast Response
  € 25
Great choice if you want to learn the game!

FOR SALE OR SWAP
All these computers are for sale or can be exchanged for specimens that are not yet part of the museum.