Not surprisingly, hybrids stood out on the list of the most environmentally friendly vehicles of 2008, as compiled by the American Council for an Energy-Efficient Economy (ACEEE). Although a limited-production vehicle that runs on compressed natural gas (the Honda Civic GX) took top honors, the ACEEE’s 10 greenest vehicles include four hybrids:  Toyota Prius, Honda Civic, Nissan Altima and Toyota Camry. The conventionally gasoline-powered Smart ForTwo, Toyota Yaris, Toyota Corolla, Mini Cooper, Ford Focus, Honda Civic and Honda Fit rounded out its top 10.

Hybrids continued to rank high, even though the U.S. Environmental Protection Agency’s new fuel-economy calculations more realistically assess their gas mileage.  “Sales rose by a whopping 40 percent last year,” says Shruti Vaidyanathan, ACEEE’s vehicle analyst. “This interest in hybrid vehicles should shine the spotlight on other green-vehicle technologies that can significantly improve fuel economy.”

ACEEE also named the “meanest vehicles”—those that have the worst environmental impact. They included the diesel-powered Volkswagen Touareg; the Mercedes GL320 CDI, R320 CDI and ML320 CDI; and the Jeep Grand Cherokee.

The independent, nonprofit research organization rates cars and light trucks every year by calculating emissions, fuel consumption and greenhouse-gas production for each model. You can view the green score for widely available models in every class—including pickups and SUVs—by clicking on “Greener Choices” at the ACEEE Website, www.greenercars.org.