Hypermiling is trying to get an absurd amount of miles per gallon out of your vehicle of choice, and practiced by a group of dedicated fuel-economy enthusiasts.  They are probably a pain to drive around or talk to, but as with all enthusiasts, they have developed a set of techniques and a philosophy that we can all learn something from.  Of course, they seem to prefer the hybrid cars, and claim to have gotten upwards of 100 mpg (backed up with photos of their car's electronic readouts) in some of them.  I know that my 2002 Ford Explorer was rated at 16 mpg city and 21 mpg highway, but with just a couple of their techniques, I've been averaging 24mpg over the course of a tank instead of the 18 or so that I used to get.  Check out the link and see if there is anything you can do to help your own fight against the gas lords, because you never know what you just might learn.  For instance, I learned today that the tire pressure number on the driver's door jamb isn't the optimal number for safety, handling, and performance.  It also includes things like noise and ride quality.  I guess it makes enough sense that the max number on the sidewall of the tire is well within the safety and wear limits of the tire or it WOULDN'T BE LISTED so high.  Sheesh, the things that'll make me feel stupid.  I'm gonna go check my tires now.