We only see "real dark" when a storm takes our power away. There is something that is quite frightening about looking out into total darkness with no street lights, porch lights or house lights.

For billions of people in the world the only source of light for their day is the sun. When the sun sets their world become one of total darkness, save the flicker of a candle or kerosene lamp. Some very ingenious people have developed a way to light that darkness.

It is based on the same principles as your Grandmother's coo coo clock. It uses the force of gravity pulling on a bag full of dirt and rocks to light the night. I think this idea is just crazy enough to change the world.