Urine-powered fuel cell socks: The must-have pair of socks this Christmas
The invention uses microbial fuel cells powered by the operator’s fresh urine.
http://arstechnica.co.uk/science/2015/12/urine-powered-fuel-cell-socks-the-must-have-pair-of-socks-this-christmas/

The researchers from the University of the West of England (UWE Bristol) have created a self-sufficient energy producing system in the form of a pair of socks with 24 miniaturised microbial fuel cells (MFCs). The cells are powered by fresh human urine pumped by the user’s footsteps, so you might still need to waggle your feet around once in a while.

In the experiment described in a paper published in the Bioinspiration and Biomimetics journal, the researchers managed to power a wireless transmitter with the energy produced by the socks, which sent a signal to a PC every two minutes.

“This work opens up possibilities of using waste for powering portable and wearable electronics,” said Professor Ioannis Ieropoulos who led the experiment. “For example, recent research shows it should be possible to develop a system based on wearable MFC technology to transmit a person’s coordinates in an emergency situation. At the same time this would indicate proof of life since the device will only work if the operator’s urine fuels the MFCs.”