As if cell phones don't already encourage enough annoying, disruptive public noise, researchers at Sungkyunkwan University in Seoul have developed a phone battery that you charge by yelling at it.
The battery has zinc oxide wires running between two electrodes; sound vibrates the wires, and that creates electricity. Right now, it only works with sounds over 100 decibels, which is unfeasibly loud — think motorcycle, chainsaw, or train. (It would be good for motorcycling rail-riding lumberjacks, though.) But in theory, batteries like this could charge off the sound of your voice, or — ideally — the obnoxious cell phone chatter of the people around you.
The best part about this: It harnesses the human instict to shout at things that aren't working. Phone runs out of juice, you yell "goddamit, phone, no, what the hell?!?," phone has juice again. Go science!
Mobile phones could be charged by the power of speech, The Telegraph.