Here are some quotes from the fascinating article I'll be reading over lunch, The Power Within by Bob Holmes, in last week's [tag]New Scientist[/tag].
Your body is buzzing with energy, so why not steal a little to run those electronic gadgets you can't live without.
The food you eat packs as much energy as a thousand AA batteries.
The human body generates upwards of 100 watts of power. If energy-scavenging devices could collect some of it, they might make batteries redundant.
Thermoelectric patches could produce enough power to run your iPod.