I know you're probably thinking -- oh great, another post about some silly looking USB keys. Well guess what -- they're not USB keys!
These are batteries, and in my opinion quite possibly the greatest things ever made. That's right -- they're USB rechargeable AA NiMH batteries. Plug it into your laptop, XBOX360, Wii, monitor -- whatever has a usb port, you can charge your batteries on. And apparently they can still be charged on a regular battery charger too!