The diminutive Nipper charges your phone with two AA batteries

There are already plenty of external back-up batteries for smartphones, although they won't do you much good if they've lost their charge by the time you finally need them. That's where the Nipper comes in. It provides some extra juice to your phone via two easily-obtained AA batteries, and is much smaller than most other AA-powered chargers we've seen. The Nipper consists of a couple of modules that are linked by a strap. When not in use, those modules snap together via integrated neodynium magnets, forming a block slightly larger than a sugar cube.