What a great site! Looks like we've got the same ideas and goals, but far different vehicles/motivations. 1998 Ford Explorer Sport, 2 Wheel Drive, 4.0L SOHC, Auto, 3.73 limited slip, 18MPG factory, my worst 20, my best 24.99. 12 mile commute (for the wife) and we take this vehicle on the longer trips. AC on, cruise locked at 65mph. As a PCM tuner, I've managed to electronically boost the efficiency, but now I need to work on "me". 2005 Ford Focus, 2.0L Duratec, 5 speed, 28MPG factory, 34 MPG average, 37mpg best. 65 mile (one way) commute in to Seattle. I drive at 65-70MPH in the far left lane . If I'm going to change anything, it's my speed. Just have to make some flashing lights and a warning label for the tailgate so I don't get rammed off the road when I start riding the far right white line and drop to 55MPH... I've been concentrating on the mechanical aspects of the mileage game, but had NO idea there was so much to be gained from changing driving styles. Free flowing exhaust, intake, widen the gap on the plugs, keeping tire pressure up have all made some gains, but most of you are seeing 3x that in just changing your driving styles. I'll be lurking for a while to see what "pearls" I can gleen from the posts, and I'll be sure to post my results.