Energy from human fat
Yes Men: http://www.scoop.co.nz/stories/WO0706/S00281.htm and https://vimeo.com/129357544
Perpetual Motion. Robert Park. 28 Jun 2002. “Free Energy, APS speaks out on Perpetual Motion”. http://bobpark.physics.umd.edu/WN02/wn062802.html
Playground. Mike Wendland. 3 Mar 3, 2003. Kiddie Power. Detroit Free Press.
Soap. Michael Steen. 16 Sep 2002. A squeaky clean future for the car? Reuters News Service.
Sugar. Teresa Riordan. June 21, 2004 A Sweet Way to Fuel Cars. New York Times.
Thermal depolymerization. Garbage in, less garbage out (as fuel) is an energy sink as well as a perpetual motion machine.
Tires-to-oil. Jeff Clark. 2 May 2000. http://groups.yahoo.com/group/energyresources/message/715
Tornadoes. 29 Sep 2005. The Power of Spin. The Economist.
manure, turkey guts, etc.