This is really just economics, not faith and economics. And in fact, it is mostly just a really cool map. If you follow this link you can actually zoom into gas stations near your house or job and see which prices are the cheapest near you. Really neat.
If you are less interested in following the link, areas in dark green have gas less than $3.28, dark red more than $3.78. BTW, I drive a Prius. I'm just saying.