There's a cool device out there called the proporta. It's a small battery about the size of an ipod so -- 2.5 by 4 by 1 inches that can charge portable devices through a usb port. The battery is 3400 mah and can also be charged from a usb port or from an a c adaptor. It's smaller than an icon and could give you 2 extra charges or including the icon's battery 3 times the normal battery length. Just figured some people might want to know about it.