"Switching from an average car to a 13 mpg SUV would use as much energy as leaving your refrigerator door open for six years."
According to the Sierra Club, driving an SUV is equivilent to:
Leaving a fridge open for 6 years, leaving the bathroom light on for 30 years, or leaving the TV on for 28 years. (No idea how a TV is similar in usage to a lightbulb.)
http://sierraclub.org/globalwarming/SUVreport/