This post is by Sheryl Canter, an online writer and editorial manager at Environmental Defense Fund.

The idea of generating electricity from human movement isn't new, but recent advances make it practical in a way it never was before. This CNN article gives a good overview of how the technologies work, and where they are in use. For example:

• The California Fitness gym in Hong Kong captures energy from workout machines to power lights and music. The technology was developed by French inventor Lucien Gambarota. Another human-powered gym is set to open this month in Portland, Oregon.
• A London nightclub called Surya uses a special dance floors to convert vibrations into electricity. Another vibration-powered club will open next month in Rotterdam, Netherlands.

The floor technology can be used in more than just dance clubs. Any large crowd will produce vibrations. Sustainable Dance Club also has received requests for floors from bus and train stations, where it can be used to power lights and display boards.

And there's more!

Other types of human activity can produce vibrations. From an article on Treehugger:

Vibrations from passing trucks, the rumbling of speeding trains and even the footfall of busy city commuters could be captured and converted into energy to light walkways and buildings, engineers say. A London-based architectural firm is working on a project that aims to harness the pulse of a city and use it as a renewable energy source.

Nor is energy from workout machines limited to gyms. This past June in Yokohama, Japan, a non-profit group held a concert powered entirely by pedaling. Audience members took turns on four refurbished bikes attached to generators.

In case you'd like to try this at home, here are instructions for adapting your bike. Or if that looks too hard, check out Windstream Power. You can find a long list of human-powered devices and manufacturers on the PureEnergySystems Wiki.

To bring technologies like these into the mainstream in the U.S., we need the economic incentive of a cap-and-trade bill. Once the rules of the game are clear, investment dollars will rapidly increase.