The 2-liter plastic bottle solar light bulb is an genius way to light up a room while reducing the amount of power you consume through creative recycling. Recently, a group from Manila called Isang Litrong Liwanag (A Liter of Light) got together to build and install solar lightbulbs in a 500 house pilot program. Not only do they get better lighting, but they can spend the money they save on other, more important expenses. It’s amazing what a little sunlight can do. [via NTD]