Bridge Vibration- As cars pass over a bridge they cause vibrations, which are picked up by attached magnets. The motion of the vibrating magnet inside inside a coil of copper wire produces an electronic current.
Energy harnessed: 20 to 120 microwatt
Rain Power- French researchers found that when raindrops strike a strip of material that is sensitive to electronic, they can generate a tiny but steady current powerful enough to drive micro electrical devices.
Energy harnessed: 1 microwatt per drop.
Electric Nanofibers- Scientists developed yarn made out of electricity-receptive nanofibers. When strands of yarnare rubbed together they produce a current, allowing clothes to provide power.
Energy harnessed: Potentially up to 80 milliwatts per sq m of clothes.
Max Donelan knee brace- "When you walk, one set of muscles drives your legs forward, while another does “negative work” by pulling in the opposite direction to control your stride. Now, researchers in Canada and the US have built a device that can convert this negative work into electricity. They claim that the device, which straps onto the leg around the knee, can generate 5 W of electricity — enough to power several mobile phones or even an artificial limb." -physicsworld.com