This lantern is said to have a very efficient wind-up mechanism. Apparently, you can get thirty minutes of ambient light from a minute’s worth of winding. The light can be placed on a flat surface, or hung up using the recessed loop. You can also charge it via a 12V car socket. Available from I Want One Of Those (£19.95). Found via: TreeHugger
Freeplay has also a windup lantern. Freeplay is (I think) the original company that came up with the windup technology for flashlights.
http://www.freeplayenergy.com/indigo.html
For anyone in Australia, these are available at much lower prices at hardware stores such as Bunnings and some camping stores.