Pretty cool!

http://gizmodo.com/5715616/the-credit-card-knife-is-for-the-truly-unbalanced

That's really cool but obvious why it's made like that.. LOL. A simple sharp peace of carbon fiber shaped like a credit card with a magnetic strip would be really hard to detect... Man, I just scared myself.....

That's really cool but obvious why it's made like that.. LOL. A simple sharp peace of carbon fiber shaped like a credit card with a magnetic strip would be really hard to detect... Man, I just scared myself.....

looks like a metal blade to me...  PROVE ME WRONG!!!

Yeah that's what I meant. But a carbon fiber one would be crazy cool. Plus nondetectable with metal detector if they made it out of carbon fiber. I seen some carbon fiber knives once, really cool....haha gotta be careful not to put the wrong card in the bank machine...

That is very cool.

they have ceramic knives....

though via wikipedia:

Ceramic knives may present a security problem as ceramics are not seen by conventional metal detectors. To hinder misuse of concealed knives many manufacturers include some metal to ensure that they are seen by standard equipment. Ceramic knives can be detected by extremely high frequency scanners (e.g. millimeter wave scanners) and X-ray backscatter scanners.

These knives are usually produced by dry pressing zirconia powder amd firing them through solid-state sintering. The resultant blade is sharpened by grinding the edges with a diamond-dust-coated grinding wheel. Zirconia ranks 8.5 on the Mohs scale of mineral hardness, compared to 6 to 6.5 for hardened steel, and 10 for diamond. This very hard edge rarely needs sharpening.

May be better to just sharpen one corner of your CC

Held firmly corner out will cause damage worse than a paper cut....