I ran across this Web site that will tell you, using today's average gas prices, what the average cost would be for a round trip to a location. For example, did you know that a trip from New York to Los Angeles costs $346 in a Hummer H3 and $111 in a Toyota Prius? They love showing that on their site. For example, I used this once when a few friends and I took a trip up north, it allowed us to budget for gas pretty exactly. Sometimes it is a little sobering to see how much a commute really costs you in gas - for example, I showed this to a co-worker, and he realized that he was paying $6 a day in gas just to get to school...and that's before tolls and wear and tear on his car.