Some guy went and made a wallet out of an old SNES game cartridge (that shit better not have been A Link To The Past). The cartridge comes packed with emergency LEDs, videogame sound effects, and enough room to carry cash, cards, keys and a USB memory stick. Granted, it's not the coolest wallet I've ever seen, but I'm biased since I made one out of an entire Wii console. Plus, if i rock it in a front pocket, it makes my junk look bigger. And rectangular-er. Which, according to my latest poll, 6 out of 5 women on the bus find freaky deaky.
Hit the link for a picture of the insides and a link to the Instructable.
Super Nintendo cartridge wallet with sound, light, and key storage [instructables]
Super Nintendo cartridge wallet: you probably want this [engadget]