Jmengel has built a USB charger from an old CD drive, a rubber band (from broccoli!), and a name badge strap. The device stretches when you breathe in and converts the motion into a five volt DC output.

The concept is simple but the making part is a little scary, involving the design of drive trains, circuit boards and lots of fiddly work. This first version only puts out 50mW, which means that you would take around a day to charge a cellphone, but the intention is noble, and there is a Version 2.0 on the way.

Lol so if you die, your phone dies with you.