Sea creatures are inspiring the latest devices that harness wave power. This one called the oyster, sits on the sea floor, and opens and closes as waves pass over it. Cables attach it to generators on the shore. Since the November 2009, it's been powering 9000 homes in the Orkney Islands. Another device looks like a snake. The anaconda is made from a rubber tube filled with water that floats just below the surface. When the swell hits the front of it, the tube squeezed above ripples done its links and powers a turbine in its tail. Prototypes are currently being tested, but the full-scale version will be 2000 meters long. This system also looks like a snake. But this one is made of steel. It floats near the surface, where waves make its joints move, this drive hydraulic system that power electrical generators, like the anaconda. It's still being tested; results will prove that these devices are up to the job of supplying variable sources of green energy.