Under an electron microscope, the strands look like the bristles of a very small brush, and they have the seemingly magical piezoelectric property of producing a tiny electrical current when moved or squeezed. Put billions of them together, and you get enough energy to power devices without using an external source of electricity.

"We turn motion into power," says Wang. So far, HONG devices have lit LED lights, run calculator LCD screens and powered rudimentary electronics in the lab. That's just the beginning.

Wang and his team are working on creating HONGs that can power complete wireless devices. Their current project is to make self-powered environmental sensors for a variety of uses.

For instance, the Georgia Tech team is working on a sensor that could be embedded in a bridge. "Surrounded by concrete, it wouldn't be easy to change the sensor's batteries," Wang quips. But with a HONG generator inside, the sensor could be powered by the vibrations of cars and trucks driving over the bridge.

The idea is that every 30 minutes, the sensor -- and dozens like it in the structure -- would send a reading to a receiving station for analysis. If the sensors showed that the bridge was in danger of collapsing, the structure could be shut down, preventing a disaster like the 2007 collapse of the Mississippi River Bridge in Minneapolis.