Houston Auto Show's 'green' options.

When it comes to buying a new car or truck, it's a little easier being green than it used to be. Just take a walk through the Houston Auto Show, which opened Saturday. Sprinkled among the 600 vehicles on display are a range of alternatives to traditional gas-powered models, from big trucks to thrifty compacts. Whether it is a gas-electric hybrid, a "clean" diesel or a "flex-fuel" model that can run on gas or ethanol, there is something for every taste and budget.