The Nokero solar light bulb sits outside all day, quietly soaking up the suns rays. Then, once the sun goes down, it turns on and provides you with light, not costing you one bit of electricity.
The $15 bulb provides about 2 hours of light on a day's charge, although it can be fully juiced up to provide 4 hours if need be. It uses five energy-efficient LEDs to provide its light while using 1/200th the energy of a traditional fuel light. Sure, it won't last all night, but it's perfect for hanging out after the sun sets.