An example of suppressed technology.

"Cost is not the issue either Even after being hand made with “exotic” materials in an intentionally limited edition, the Xl1 still only costs $60,000. There is a lot more of a market for this car than 2,000 units at that price, have no doubt, this car is being held back on purpose. If it can be hand made for that little, automated assembly lines could do it for half. And if a 1,700 plus pound Xl1 can get 300 mpg, a 3,400 pound Chevy Truck should be able to deliver at least 150 MPG, the Xl1 lays the mileage scam bare, with every hybrid that gets 40 mpg and every truck off the line that gets 20, Americans are getting the shaft and they do not even realize it."

http://worldtruth.tv/volkswagens-new-300-mpg-car-not-allowed-in-america-because-it-is-too-efficient/