When I have a 10 hour drive to do, I find that I start out in a gas-conserving manner and lapse into I'm-tired-of-this-drive-as-fast-possible after a few hours, so I end up getting only about 45 miles to the gallon, varying a bit with how much I need to crank the A/C.

At $4 a gallon, that's 12 gallons of gas, bringing the cost of a drive to Maine to $71.43. Cheaper than a plane or train, but it can be agonizing trip if you run into traffic and spend 2 hours going through NYC or inching down the NJ Turnpike because everyone in the entire world is getting off at exit 7 to go to the beach. My 5am trip north took 10 hours, and my 4am trip south took 13 hours.

Tip: Don't buy gas at rest areas in Connecticut. It was $4.50 a gallon when I passed through yesterday. Zip through New York to New Jersey, where it was $4 a gallon (although you're not allowed to pump it yourself, so you have to sit in a 10-car-deep line while a wholly disinterested Exxon employee pumps it for you).