Hello,
I'm on the east coast, but no where near the DC area.
I heard a pretty lame story on NPR today (I'm a bit shocked and surprised, really). All they said was you need to change your driving habits, and the people who practice hypermiling are sorta' crazy nutcases! They talked about driving barefoot -- but they didn't even mention tire pressure.
'Hypermilers': Squeezing Out Every Mile Per Gallon