The Amazing Joule Thief Circuit, by Ken Killeen of Terran Sky

"A joule thief is a minimalist Armstrong, self-oscillating voltage booster that is small, low-cost, and easy to build; typically used for driving light loads. It can use nearly all of the energy in a single-cell electric battery, even far below the voltage where other circuits consider the battery fully discharged (or "dead"). Hence the name, which suggests the notion that the circuit is stealing energy or "joules" from the source. The term is a pun on the expression "jewel thief": one who steals jewelry or gemstones.The circuit uses the self-oscillating properties of the blocking oscillator, to form an unregulated voltage boost converter. The output voltage is increased at the expense of higher current draw on the input.", courtesy of Wikipedia, 2014.

...or you can watch my little video which is admittedly far less complicated and shows the device in action.
I hope this inspires you to think differently about energy and power. I hope even more, that some one out there goes on to innovate something great with it!
So please enjoy a quick demonstration of a couple of 'joule thieves' which I made at home.

By Ken Killeen of Terran Sky
www.facebook.com/My.Terran.Sky