Earth-friendly cars

Mayors from around the world met at U.N. World Environment Day 2005 in San Francisco last week to create a plan for a sustainable urban future. At an opening day festival for the event, more than 60 companies showed off fuel cell-powered vehicles such as the new Honda FCX. Other carmakers showcasing fuel-efficient vehicles included Nissan, GM, DaimlerChrysler and Toyota.

Honda's fuel cell stack provides power to the compact car. It can operate at temperatures as low as 4 below zero and as high as 203 degrees.

The 705-pound ZAP Intimidator LUV electric car is more diminutive than intimidating. ZAP stands for "zero air pollution."

If the Intimidator is still too big for you, the company's Zappy Xpress scooter might do the trick. The $399 Xpress zips along at 17 mph and can travel up to 20 miles on a single charge