What can you do with an Altoids tin?

Over at Craft Wonderland, I started a new thread on creative uses for mint tins.

I'm currently using some to hold D&D dice, a barebones first aid kit, Splenda, a basic bike travel kit, and some other stuff.

The internet gives many more creative uses, including an Altoids tin wallet or a thumb piano. If you like gadgets,you can go high tech! Try a mp3 player, flash drive, mouse, or a battery pack for an external hard drive that runs on four AA batteries! You can even go retro and make a Morse code oscillator. (Not practical, but it sure is geeky!)

Here's one I may try: an iPod charger. There are multiple versions; one uses only one 9V battery, while more sophisticated versions use combinations of batteries.

What can YOU think of? Why don't you come add it to the list?