People in the Philippines have found a great way to save money and save electricity. Electricity in the Philippines is the most expensive in Asia, accounting for a significant proportion of poor peoples expenditure. One budding entrepreneur has overcome the problem using only a small piece of metal, a plastic bottle and water (cost about $1). By filling the plastic water bottle with water and putting through the roof of the house, light naturally refracted around the room, stopping the need for artificial light and paying for electricity.

http://www.bbc.co.uk/news/world-asia-pacific-14967535