GravityLight is a new LED-based lamp that is powered much like a cuckoo clock…a bag of sand (or anything weighing about 20lbs) is pulled down by gravity, generating electricity to power the LEDs for about half an hour. It’s a neat idea for developing countries. The project is being funded via indiegogo, and have already surpassed their funding goal (with 33 days left in the campaign).
(read more at FastCompany)