If you know how to pick locks this might be a good addition to your wallet, the Titanium Entry Card. If not, start here.
The Titanium Entry Card is made out of a single sheet of aircraft grade titanium and comes with two identical rakes, two picks, and two tension wrenches. This credit card sized lock pick set is only .032 in. thick and is non-magnetic. This might just be the perfect wallet lock picking set. Never be locked out of your house again.