I've used a money-clip for years as an alternative to a wallet, and the idea of having a small, sharp blade (Gerber makes great tools!) built into it is immensely appealing, especially given the copious positive reviews for Gerber's $19.26 version (but I worry that I'd forget it and lose it to a TSA checkpoint).
Gerber 31-002521 GDC Money Clip
(via Wired)