This is what Steorn claims to have discover and they are challenging Scientists.
You can read infos on their website but I have also looked at finding if it's a new scam or not so you can read the "Sciguy" opinion that is quite the one I would say as well :
"The more I think about this I am of two minds:1. These guys really do think they've succeeded in breaking the laws of thermodynamics.2. Recall that Steorn is a former e-business company that saw its market vanish during the dot.com bust. It stands to reason that Steorn has re-tooled as a Web marketing company, and is using the "free energy" promotion as a platform to show future clients how it can leverage print advertising and a slick Web site to promote their products and ideas. If so, it's a pretty brilliant strategy."
Read more at blogs.chron.com/sciguy/...