"USB devices do everything these days, including charge your gadgets with only the power provided by your breathing: specifically, the act of moving one's chest in and out. Just in case you thought this required sticking a gadget down your throat, see the image above and note that it's attached to the outside of the model's chest. The instructions for building your own breathing powered USB charger are over at instructables, and the kit only requires simple equipment like a spare CD drive, some elastic bands, and an electric circuit. You've got all that lying around, ain't ya? Well then, stick it all together and get breathing. Unfortunately, it only produces around 5 volts, so you'll have to breath a lot whole lot to get any meaningful charging time from this invention. And don't even think about attaching it to the cat."

[Via engadget]