While posting in his blog about ways to increase fuel economy
goes into considerable depth covering the offbeat tip of buying your gas in the morning instead of the afternoon. The theory goes that fuel is denser in cooler temperatures and that you get more fuel for your money if pump in the morning when the temp is low and the fuel is denser. der5er, suspicious of the tip, did some research and after considerable effort finally found Chris Lawson's calculations
on the subject. It turns out that it might be possible save 45 cents per gallon of gas if stations
stored their fuel above ground, which most don't, and you were filling a tank the size of a KC-10 refueling aircraft. Still sounds like something Jamie and Adam would have fun disproving on MythBusters.
[Source: der5er, chrislawson.com]
UPDATE: changes made