Rolamite

The above is taken from The New Book of Knowledge Annual 1969 (Grolier Inc., 1969).  According to Wikipedia:

"Rolamite is a technology for very low friction bearings developed by Sandia National Laboratories in the 1960s. Invented by Sandia engineer Donald F. Wilkes and patented by him on June 24, 1969[1] these devices use a stressed metal band and counter rotating rollers within an enclosure to create a linear bearing device that loses very little energy to friction. One source claims it is the only basic mechanical invention of the 20th century.[2] Tests by Sandia indicated that Rolamite mechanisms demonstrated friction coefficients as low as 0.0005, an order of magnitude better than ball bearings at the time."

It apparently vies with Toribio Bellocq's 1927 wave pump as the last century's contribution to basic mechanical inventions. Curiously, for such an apparently important innovation, it does not appear to have found many applications in the decades since its invention.  (There are those that believe that the technology was purposely suppressed.)  The Sandia National Laboratories site does report that rolamite switches were used used on a nuclear warhead to detect the missile’s acceleration pattern en route to a target, and subsequently found a somewhat more pro-social application in the first automotive airbags. As for the inventor, he was reported to have founded Rolamite Technology Inc. in the 1980's but the web has nothing else to say about him.  Lots of fodder here for conspiracy theorists.