Everyone these days has a digital camera, and every digital camera has a memory card of some kind, which are insanely small, hold a ton of pictures, and are way too easy to lose. SD-cards (Secure Digital) are one of the most popular and widely uses memory-card formats, available in mp3 players, camcorders, phones, cameras, and handheld devices.
Chances are you will have a few of these things floating around the house, so wouldn't it be nice to have some way to store them and have them with you if needed? Instructables features a project to make a simple wallet-card that will hold your memory cards in place and store them for travel.
SD is not the only card you can use with this, you can cut it to be any type of cards you like, and most of them will be thin enough to fit in your wallet. Check it out!