Gravity powered lights, cheaper than solar

Simple things that we take for granted, like flipping a switch and having light suddenly appear, aren't so simple in developing countries. This fantastic gravity powered light may change that, if their Indiegogo project is successful.

The designers developed the project in their spare time over four years, while working at London-based design firm Therefore. They're expecting the light to cost less than $5 to manufacture at scale. Once a family purchases the light, they'll be able to keep it running at no additional expense.

(Thanks, Thom!)