I second Nate Kranzo's credit card vanish, excellent work!
David Acer has a nice routine (can't remember where it's published-I wanna say one of the Natural Selections books), wherein a credit card vanishes in full view from the top of an ungimmicked wallet, and is found INSIDE the wallet, though with work it could be made to travel to a pocket. No gimmicks!
Greg Wilson has a nice card vanish which he uses i na couple effects from the 'In Action' series.
One could very effectively vanish a credit card by lapping it under some suitable misdirection.
Tenkai works fine for me
CL