Saw a news seqment the other day where they ran two Prius's (or is it Priui?) from Chicago to New York.
One was driven by a self-described "Hyper-miler" who gets off trying to squeeze the most miles out of a gallon of gas and the other was driven by a news staffer who "drove like a normal person" at or slightly above the speed limit.
The results astounded me. The normal guy had to fill up the ten gallon tank once on his way and wound up with an average of something like 40 miles to the gallon.
The hyper-miler finished with gas to spare in the tank and an average of over 70 mpg.
He listed three tips, one of which I have forgotten

, but the other was slow down. The final one was keep off the brakes. Drive in such a way that you use your brakes as little as possible and you will save gas.
I tried that recently and it seemed to work pretty well. Adopt a sufficient cushion between you and any car in front and you can do a lot of coasting and slight downshifts (probably not the hyper-milers practice in his auto-prius) and you can roll for miles without touching the pedal.
Anyway, since we were talking tips....
D