I have been trying somethign similar with my MINI lately. I got so tired of people seeing me at a gas station and being all "wow, I bet that thing gets great milage" or "Man, I bet you love that car with these high prices" And having to explain that I was gettign around 21 city and 28 highway and that the best I ever got was just over 30.
So, I decided for at least one tank to see what it could really do and I have been doing my best to drive like there was an egg under the accelerator, try to really anticipate lights and coast as long as possible and keeping it below 70 (right now I drive about 18 miles each way to work a day, 6 city and 12 highway and average 26 mpg). Plus with the MINI, I have the added advantage of being able to whip through corners really fast so I do not need to slow down as much.
It has been a boring couple of weeks, but so far, it is getting much better range. It is hard to really tell as the guage travel is very non-linear, but I seem to be getting about 25% better milage or more. I will report back in a few more days.
I really don't care about the money as in the scheme of things it is not that much, but I might just try to start cutting the engie at stoplights next time just to max it out. Maybe I will go to the Prius ultramileage site for more tips.
Not, it is just too boring for all the time.