Several years ago we developed a controller for creating a match museum game. There could be up to five pairs of associated items, and if the visitor got them right by pressing associated buttons, there would be a simple pay off. A light would light up or an audio message would be played. More recently, we have developed a general purpose interactive controller with 10 inputs and four low current (under 500ma) sinks, as well as four more low current outputs that could be upgraded on the PCB to relays outputs capable of handling 2.0amps at 30vdc. The program in either one is fairly flexible to customer requirements. Click on either one and see if you might be able to use it in your next economical interactive exhibit.