The card game Dominion has a lot of cards. It also has a rather unique mechanic, in which you only select some of the cards for each play. You can find a lot of helper programs for randomizing the set of cards for a given game, and they are very convenient. However, you still need to find all the required cards in the box, and after the game is done, put them back.

To make that easier, I plan to add LED lights to the tabs separating the different cards. Some simple electronics and I can make it highlight the cards that have been chosen for the current game, and later make it highlight the places where I need to put them back.