expertbattery via eBay offers the Generic 10,400mAh Power Bank Battery Pack in Black or White for $19 with free shipping. That's $3 under last month's mention and a buck under the lowest total price we could find for a similar battery pack elsewhere. It features 1A and 2A dual USB output and a built-in microUSB cable. It works with iPod, iPhone, smartphones, digital cameras, and other devices.