If you don't have electricity or live in a home with no windows, it's going to be dark inside, even during a sunny day. Luckily, a bottled liter of water with some bleach can provide approximately 55-60 watts of light from the sun. This simple idea has helped many dwellers in the light-deprived slums of the Philippines. "A Liter of Light" is a sustainable lighting project by Illac Diaz which aims to bring the eco-friendly Solar Bottle Light to disprivileged communities worldwide.