Researchers in Japan and Germany have converted energy from soundwaves into electromagnetic energy, trapping a magnetic "spin current" between metal layers. In the experiment, when sound waves are directed at an interface between the thin metal layer and magnetic material, electrical signals are generated at a pair of electrodes attached above. When the soundwaves reach the magnetic material, this creates a spin current that gets picked up by three layers of metal. This is where the exercise class-sounding reverse spin Hall effect kicks in, transforming it into an electrical voltage.
http://www.engadget.com/2011/09/20/researchers-convert-soundwaves-into-electromagnetic-energy-sile/
See Also
Electricity from Light
Electricity from Water
Tesla - Electricity from Space
What Electricity Is - Bloomfield Moore
What Electricity Is - Keely
What Electricity Is - Pond
What Electricity Is - Russell
What Electricity Is - Schlosser
What Electricity Is - Steiner
What electricity is - Stranges
What Electricity Is - Tesla