The Economist tackles perpetual motion machines in an article appropriately titled “Perptual Nonesense“. It should be noted that inventors have been pursuing this dream since the beginning of our patent system. Here’s what one patent attorney thought about it a century ago:
“The solution of perpetual motion apparently still captivates those who believe in the possible successful solving of such a machine, though the vain efforts of centuries have done nothing beyond showing failure and the wanton waste of energy and money from its votaries. That this Will-o-the-Wisp is still being pursued is evidenced by the continuous so-called new discoveries which are launched with great regularity as the “Eureka” of some mechanical mind”.
Source: The Inventor’s Universal Educator by Fred G. Dieterich, Washington, D.C., 1911.
Patent Librarian's Notebook 
Even the phrase “perpetual motion” annoys me, but not for the obvious reasons. I can excuse the uneducated, bumbling free energy seeker for the use of the term, but even those educated on the subject continue to use a term they do not understand.
Perpetual motion is not something which is in need of discovery. It is all around us. We live on it. The earth has been in perpetual motion about our star for billions of years, due the to frictionless environment in which the forces which act on it do so. And do not anyone say to me that the earth shall eventually wind down. It surely shall, but if anyone invents a machine which runs for even one hundred millionth as long as the earth with out requiring additional energy, everyone will concede, it is indeed perpetual motion.
This is what bugs me. Perpetual motion is useless. It provides no free energy to satisfy our energy hungry world community. The goal of these researchers, both learned and unskilled, is not perpetual motion. It is instead, a source of energy which is clean and for any practical reason inexhaustible. Such a source of energy is what learned people, evidently, even librarians, incorrectly refer to as “perpetual motion.”
As for the possibilities: The fundamental forces of nature provide many promising leads. From the twin subatomic forces which govern atomic structure, we have already found a means by which we can harvest vast quantities of energy from minute quantities of matter which is other wise worthless.
The other two fundamental forces of nature are just as mysterious. Both gravity and magnetism exert measurable and significant force against mass for indefinite periods of time. Gravity does the work that otherwise would take definitive quantities of fuel. A definitive amount of fuel accelerates only a definitive quantity of mass. While gravity accelerates an infinite quantity of mass; and after having done so, instead of being diminished even to a small degree, the force remains unabated in the slightest.
Both string “M” theory and the standard model provide descriptions of gravity and magnetism's interaction with other energy and matter, but neither even attempt to explain the source of their power.
Do not scoff at the intrepid explorers, both educated and unskilled, for their efforts, guided by the love of money, not withstanding. Many unskilled and unrespected have given us great intuitions. Need I remind anyone of Albert Einstein's esteem prior to 1905?
It is not beyond reasonable practicality that you and I may someday soon or in the distant future, live our lives in the comforts provided by an abundant source of free energy for which we have to thank those whom we now scoff.
Those who laugh now, prepare to eat crow. You are lucky if it is not in your lifetime that unlimited free energy is discovered. It is truly sad to say such a thing. All should be so lucky to have this discovery in their life time. None should scoff.
Jerry Wickey
Jerry, I agree with you 100%. Your last paragraph, especially. Nobody could have said it better.