There is some debate about exactly how much juice this contraption generates, but let's face it: the best way to generate electricity is through your own exercise. It's good for you and the environment.

Of course, what you power with all that human-generated electricity is debatable. A couple of cell phones and my laptop and I'd good to go, but some of you need even more power. Either way, leave your experiences in the comments.

Via TreeHugger