Your own electricity produced by wind?

I was watching CNN and they showed a report about a man that made his own producer of electricity with little turbines made out of plastic connected to a generator, and when the wind moved them, that's how they produced electricity. The whole thing was in Hong Kong. Also, he had a gym where the machines were the ones providing electricity for the gym... litteraly powered by the people exercising! Wouldn't that be a great motivator to exercise in your house?