GravityLight: Generate light with gravity
I implore people to support something far more practical like <a href="http://www.solar-aid.org/" rel="nofollow">http://www.solar-aid.org/</a> than this.<p>Solar lights are many times more thermodynamically efficient, cheaper to make, smaller and much more robust (no moving parts!).<p>This "lifting weights" thing is a silly gimmick. A lifted weight stores a miniscule amount of energy compared to a battery that's been charged by the sun.