Basically it's like one of those LED flashlights that you shake. You get light energy out of the energy you put in. Essentially manual labor energy -> light energy. As said by another poster here -- good for camping, good for emergencies -- good to have handy around somewhere or for super-poor people if mass produced. But not an energy wave of the future or anything remotely close to free energy or anything.

http://lawrencevilleplasmaphysics.com/

That's a link about a potentially huge breakthrough in fusion. No, it's not cold fusion or free energy, and is theoretically possible. It's a different kind of fusion which will at least answer some questions about electromagnetism & quantum mechanics once it gets through. It's made some progress and is supported by some big name places and is taken seriously. It's cheap fusion, too -- would be cheaper than a regular power plant and cheaper than coal -- and no radioactive waste (even the standard approach of fusion being worked on has a small amount as a by-product).