1. ENERGY EFFICIENCY
Muscle cars and trucks lose weight, tune up at Detroit auto show
The Detroit auto show doesn't have a reputation for being especially "green." Rather, the Motown event is better known as a launch pad for high-horsepower performance vehicles. But even as the demand for supercars and big trucks persists, many automakers are taking steps to slim down and tinker with their traditionally fuel-guzzling vehicles to gain better mileage.