Solar Powered Water Bottle Cap
While water and light are vital for living, this gadget joins the two together. The Solar Powered Water Bottle Cap will turn any standard water bottle (two-inch-wide mouth) like a GSI, Nalgene or Camelback, into a solar-powered lantern. Utilizing four very bright, white LED lights and high-output solar panel charges, this bottle cap creates a lantern.This eco-friendly invention is weatherproof and has a daylight sensor that turns it off automatically. It is perfect for camping. It's available for $19.99 (water bottle not included).