Meet the credit card of the future.
Built by Dynamics, these credit cards pack some serious computing power. They're one of the coolest - and most instantly practical - things I've seen at the 2011 International Consumer Electronics Show.
One of the cards includes five buttons, A through E, allowing the cardholder to set a pass code to unlock the card.
When the correct code is entered, the magnetic strip on the back is entirely rewritten digitally and is ready for use.
Without that code, the credit card can't be used.
"If you lose the card or someone steals it, it's a dead piece of plastic," Dynamics CEO Jeff Mullen told me.
Each of the cards looks and feels exactly the same as a conventional credit card. The electronics on the inside are encased in the card's thin - .033 of an inch - plastic profile. They're also waterproof, Mullen said.
The battery life is good, too, lasting four years, Mullen said. Most credits cards expire and are reissued after three years.
Another version of the card allows the holder to maintain two different accounts, say a personal and corporate account.
By tapping one of two buttons, the card's magnetic strip is again rewritten to allow access to that account.
There's also a card that allows holders to use their rewards points just like cash. Citibank announced this week that it would begin a trial run of this card.
"If you're short on cash or credit, you can use your rewards points at any merchant," Mullen said.
The cards were recognized at the trade show with one of CES's Best of Innovations honors.
Explore further: Hendersons introduce hoverboard and a future beyond wheels