That’s what the folks behind
are aiming for. They’ve built a little device, which is essentially a magnetic card writer with a user interface and biometric security. The idea is simple: buy an iCache, and then store all the data for your various cards on your computer. Download that info to the iCache, and then when it comes time to pay your bill, merely slip the included card into the reader and select which card you want it to mimic. The iCache includes a fingerprint reader, so only the authorized fingerprint will be able to program the card.
It’s an interesting idea, though I’m not 100% convinced that I’m well served by replacing all of my cards with an iPod-sized device. Still, it’s an interesting idea, and I do like the concept of securing my cards. We’ll have to see where this one goes.