In 2009, Georgian Investor Tariel Kapanadze has invented a portable device, which was likely based on the earlier work done by Nikola Tesla, that can generate 3-5 KiloWatts of electricity with little input -- you need to start the device using electricity from an outlet or battery, and once it starts, the machine could self-sustain.
5 KW of electricity would be enough to power a typical household. And such device could be modified to power the cars, buses, boats, etc.
When such device is commercially available, it could be the end-of-day for traditional energy sectors: oil drilling, refinery, natural gas, coal, etc. That would mean trillions of dollars of destruction in asset values, and hundred of billions of loss in government tax revenues.
The GDP growth in many developed countries could drop 20-30% and the pension and welfare system in many countries would collapse.
So the little device, which extracts energy from the Earth environment, would bring the end to the inflated economy all over the world. That is probably why this technology has not be widely available commercially for now.
For more, search his name "Tariel Kapanadze".
You can also check out http://www.free-energy-info.com/
Search for the video of demonstration on the Internet.
He made several demos over a couple of years, starting with a very crude prototype to the current 15KW system. He said that his invention is only the part which control the electromagnetic resonance, and the rest are Nikola Tesla' inventions.
"...suppressed by Big Oil Companies!"
Also funny, another thermodynamically impossible scheme. It's funny to consider, that Isaac Newton was as obsessed with old Christian arianism and alchemy as he was with the amazing stuff he revealed for us! Everyone just wants to believe...
Well, three hundreds year ago, you could have said: Here we go again on "Earth is round!"; or more than one hundred years ago, you could have said: Here we go again on "Plane made of metal can fly in the air".
Have you played with "Crytal Radio" when you were little kid? That science experiment demonstrate that one can harvest tiny amount of energy from the environment. Try it!