Saw this article on how the heat from a tea light candle can generate enough power to run a 25w LED light for up to 4 hours.
Perhaps the gadget will be all the rage among thru hikers in say......2020? Or even better, I wonder when the wood burning model comes out?
Portable Electricty Generator Uses a Single Tea Light For Power
http://mashable.com/2012/06/01/porta...r-power-video/