If you thought the media hysteria surrounding high-efficiency autos was something new, you’re mistaken. Five years ago, Volkswagen took the wraps off its “1-Liter Car” concept that could get 222 mpg out of a meager 8.5-hp diesel engine. Now the company is rethinking the frugal concept, as the cost of parts now looks to be substantially less than it was in 2002. We won’t hold our breath that a new “1-Gallon-Car” is arriving anytime soon, but it’s still something to think about.