I bought myself one of those metal clam-shell RFID wallets. Good thing I got it cheap from Deal Extreme ( dx.com ), because it didn't really meet my expectations. Just use keywords "aluminum wallet" and you'll find them in many styles for about $5 each.
Before I got around to returning it, I came up with an idea to put it to use: to keep my flash drives together in one case and organized. Basically, I yanked off the accordion dividers, cleaned off the glue that kept the dividers inside as best as I could, and applied a strip of adhesive-backed velcro under one lid. I cut the mating velco in smaller segments and stuck them on the back on the flash drives. Under the other lid, I used Post-It notes to label the flash drives accordingly. This way, when I open the case, the labels are aligned with the correct flash drives. You can also use Dymo labels.
Now I can carry them around and find what I need "in a flash" anytime!
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