I have a friend that is looking at new cars, and she's seriously considering a large SUV. In an effort to dissuade her, I whipped this message up tonight and sent it to her. I think it's rather enlightening.
Distance from Kirksville to Chicago ~800 miles round trip
A GMC Envoy is estimated to get 20 mpg highway (and that's probably generous).
On an average trip to and from chicago, you'll use 40 gallons of gas.
At 1.85/gallon (estimated), that's 74 dollars to get there and back.
In a car that gets 30 mpg highway (which is pretty standard these days), you'll use 26.6 gallons of gas and spend 49.3 dollars. That's a 25 dollar difference each trip.
If you go home, say 10 times a year, you've just saved 250 dollars. That's not even including driving around town, where gas mileage is even worse, and you'll spend even more. The owner of the more efficient car probably saves well over 750 bucks a year. (That's a lot of beer).
Extrapolating further, if you drove a Toyota Prius hybrid, which gets 60mpg city and 51 highway, you would spend 29 dollars per trip. That would save you 45 bucks per trip to Chicago, and easily over 1,500 dollars per year on gas. If the car lasts 10 years, you've just pocketed 15,000 dollars.
One last note_ If everyone drove cars that got 7 mpg more than they do now, the US could be completely independent of Middle Eastern oil, gas prices would plummet, global warming would slow dramtically, and and the earth would be a much happier place.
I rest my case.