EverFast USB Stick Battery Charger. It charges NiMH batteries, which are a decent eco-friendly alternative to those alkalines you are despoiling the earth with. The charger is available in AA and AAA versions, as well as single, double, and quadruple slot variations.
Wow this is kinda cool and yet so nerdy. 
Ah well…they go on to say these aren’t for sale (for some strange reason) and they are only available as promotional products. Ah well…you’ll just have to suck it up and plug the thing into the wall.
Wandering the Interwebs 