In the mid 90s I played around with incorporating electronics into magic. Anverdi had a great idea where a box would close just before a spectator selected card could be placed inside it. I didn't like the mechanics of his box, which was a box for two decks where one half was used for the electronics and the other half for the actual action. The sliding lid of the box would slowly close. Here is a video for the original Anverdi box:
After I read Anverdi's book I could build the variation...