Reprogrammable Card Can Be Many Credit Cards In One

Card 2.0

The Multi-Account credit card lets you toggle between different accounts at the same bank.Dynamics Inc.

A pair of new computerized credit cards can re-program their own magnetic stripes and hide their account numbers, providing added security for bank customers who don't want to carry lots of plastic inside RFID-proof metal wallets.

The "MultiAccount" card, which debuted at this week's DEMO conference, looks just like a normal card, but with buttons on its face in the place of that holographic eagle seen on VISAs. Users can push a button to switch between cards, and an indicator light will let you know which account you're using — such as a business account or personal account.

The "Hidden" card has five buttons and a tiny display that obscures part of the credit card number. Users have to enter a PIN to uncover the whole number and unlock the magnetic stripe, according to Technology Review. After a period of time, the numbers disappear again and the magnetic stripe is deactivated, so it would be worthless to a thief who lacks the right PIN.

The cards have a lithium-polymer battery and are fully waterproof, a nice feature for those who leave their cards inside jean pockets, sending them through the washing machine.

Card-maker Dynamics Inc. dubbed the technology "Card 2.0," noting that magnetic stripe credit cards date from the 1970s. But as Gizmag points out, it's far from the first future-y credit card to offer new consumer protections — few of which have really caught on.

Still, we particularly like the idea of one card for multiple accounts, reducing the fat-wallet Costanza effect.