Digipower has introduced its latest technology in the form of a ChargeCard battery pack. At only 3.25″ X 2″ and weighing about an ounce, the DigiPower ChargeCard is small enough to fit in your wallet like an ordinary I.D. When your iPhone, iPod, and other USB-charging devices run out of battery, simply plug your device into the battery pack’s built-in cable and you will see a small LED indicator on the side while charging.
Due to its small size, the microUSB version ChargeCard only has 680 mAh battery while 720 mAh for iPhone. The company said that it can provides two hours of additional talk time for your iPhone. Unfortunately, there is no info on pricing or availability at this moment.