David Ulrich  a friend of mine and a student at Cal Poly, recently he told me about the Shell Eco-marathon. He said  “We’ve built a car that managed to go 2752 miles on one gallon of gas (more or less, we don’t actually run the car that far, it’s extrapolated in the competition) during the Eco Marathon Americas competition.  To make a vehicle that can do something like this, improving the efficiency of every component is where we focus most of our attention.  Everything from the wheels, bearings, drive train, and (somewhat) the engine are looked at and modified in ways we think will help us out.  The car was designed to have an aerodynamic advantage as well.  Then there’s the weight factor.  Our vehicle body is made entirely from carbon fiber.  The total vehicle weight is 92 lbs, but can carry over 400 lbs.  The engine plays a big factor, but we haven’t really played around and modified ours yet due to time and knowledge constraints.  It’s pretty amazing we could get such a high fuel mileage number and know that we could probably at the very least double it if we started playing with the engine. 
This vehicle let us place second out of 30 teams during the Eco Marathon, although first was within our grasp if it hadn’t been for a little bit of weather-related misfortune.  It’s a pretty cool thing to see student built vehicles push the limits of these high-mileage vehicles every year, and if you think 2752 mpg is high, just wait a few years.”