GearXS via eBay offers the Soundlogic 2,600 mAH Portable Backup Battery
in four colors (Black pictured), model no. BB26-24/5722-ASST, for $14.99
with free shipping
. That's the lowest total price we could find by a buck. It charges and provides backup power to USB input-compatible devices, including iPhone, iPod, and most other current smartphones. Deal ends February 20 at 5:13 pm ET.
Note that this will ship in a random color.