I'm super impressed with this company Nokero based out of Denver, Co. They have developed a solar lightbulb that will help millions of people in third world countries around the world with an affordable light source [other than kerosene hence their name]. They have two models that range from $15 - $20 and replacement bulbs available as well.
Other uses with camping, patio and in natural disasters. I'm thinking about buying a couple to keep in our earthquake kit [yes I'm in So California here]