Atari 2600 cartridge storage for our public shows. It's a repurposed 8-Track tape case. The carts have to sit sideways, so we made some (admittedly simple) labels for the side held on with packing tape.
The game lineup is ever changing, as most of these were either rescued from the trash, donated from locals, or picked up at clearance prices from the local game store. We try and maintain a blend of popular titles as well as things younger people may have heard of (E.T. for example) that may draw them in to give it a try.