"Free energy" is nonexistant and anyone trying to tell you otherwise is either 1) charlatan or 2) a imbecile. There is no way to get more energy out of something than is put in. What you will want to look into are items that have potential energy ready to be used. I found this a year or two ago and I think you might be interested in this- this will be much more successful than what that pdf has it in.
[video]http://www.break.com/index/perputual-energy-light-bulb.html[/video]
Technically it is neither free nor perpetual, but it does work in small scale, and the only thing you would have to pay for after the intial building costs would be mechanical components that will break over time.
