Rechargeable batteries that charge via USB? Sure, why not? The Moixa USBCELL batteries can be charged using a regular charging station as well as the USB port in your PC, laptop, Xbox 360, or USB car charger. At this point, a USB port is so readily found in your home or office it may be easier to charge it using that instead of lugging around a charger.
Pick up two for 12.99 ($24).