At last, "rising gas prices threaten viability of biggest SUV sales". Note that many Americans are still buying inefficient vehicles and driving them farther to boot:

BTW there are plenty of online resources today for anti-SUV bumper stickers:

But note that not all cars that waste gas are SUVs - here's the top ten gas-guzzling cars and trucks of 2005:

How about making a bumper sticker with "IWASTEGAS.COM" on it - the site could hold current information on gas guzzlers, fuel-efficient cars, and simple ways to save energy. The name's available!