The American Council for an Energy-Efficient Economy (ACEEE) has named the year's "greenest" and "meanest" vehicles, along with environmental scorings of all model year 2007 cars and passenger trucks. The vehicle scores are part of ACEEE's Green Book Online, an environmental guide to cars and trucks, available at GreenerCars.com. Claiming the prize as the greenest model year 2007 vehicle is Honda's natural gas-powered Civic GX. The Toyota Prius and Honda Civic Hybrid claim spots two and three, while the Nissan Altima Hybrid and Toyota Yaris, market newcomers for model year 2007, round out the top five. The GreenerCars.com Web site also identifies a selection of top widely available models in each vehicle class. This "Greener Choices" list includes larger vehicles, such as the Ford Escape Hybrid SUV, GMC Sierra Classic C1500 pickup, and Toyota Sienna minivan. Passenger cars such as the Hyundai Sonata and Ford Focus Wagon also top their respective classes. Vehicles are analyzed on the basis of a "Green Score," a singular measure that incorporates unhealthy tailpipe emissions, fuel consumption and the emissions of gases that cause global warming. Five diesels populate the year's twelve-worst list, including the year's most environmentally unfriendly model, the diesel-powered Volkswagen Touareg. Rounding out the "bottom five" are the Mercedes-Benz GL320 CDI, Lamborghini Murcielago, diesel-powered Jeep Grand Cherokee and Bentley Arnage RL. Prominent gasoline models on the list include the Dodge Ram 2500 Mega Cab pickup, Ford F-250 pickup and Lincoln Navigator SUV. The GreenerCars.com Web site also contains informational write-ups on model year 2007 highlights, a consumer primer on vehicles and the environment, and advice on how to buy green when shopping for a new car or truck. Available to subscribers of the ACEEE's Green Book Online interactive database are summary "Green Scores" of the 1,300+ configurations of all model year 2007 vehicles, along with each configuration's fuel economy, health-related pollution impacts, global warming emissions, and estimated fuel expenses. Subscribers to ACEEE's Green Book Online can also build custom lists for comparing vehicles. Monthly and annual subscriptions to ACEEE's Green Book Online are available at GreenerCars.com. For further information, visit www.aceee.org.