Microbes Pass Valuable Gas

inimicus writes "Wired reports: 'With a reliable source of hydrogen, fuel cells can produce energy with water as the only byproduct.' The good news is that there's a functional prototype (measuring 0.7 square centimeters and less than 1 millimeter thick) that produces 1 microwatt of power -- approximately enough to power a digital wristwatch. Personally, I'm intrigued by the concept of powering my laptop with sugar-water..."