I was simply blown away by this article. Thanks @jhagel for sharing.
Your body is always generating heat, even when you are asleep. And heat, regardless of the source, excites electrons. The flow of electrons, in turn, generates electricity.
a small chip can turn body heat into electric energy, using the same technology found in solar panels. “We absorb the heat from your body, and that heat is funneled through a thermoelectric generator that converts it into electric power
Read more about the original invention, funding and development of a prototype in this article In The Future, Your Clothes Will Be A Power Plant