Here's an idea: mandate a fuel economy gauge next to the speedometer for all cars. The display on a gasoline car would show mpg, while the display on an electric car would show mi/kJ or some such. With fuel efficiency staring people in the face while they drive, they might be more keen to shut off an idling car and drive less aggressively! [DIY]
From Environmental Defense:
Check out our list of facts on cars and global warming.
Then, take action in support of national global warming action!
232 million - Number of registered vehicles in the U.S. That's almost one per person!
600 gallons - Average amount of gasoline consumed by one U.S. car each year.
12,000 pounds - Amount of carbon dioxide emitted from one U.S. car each year.
240 - Number of trees needed to absorb the 12,000 pounds of carbon dioxide emitted from one U.S. car each year.
2.7 trillion - Number of miles U.S. cars and light trucks traveled in 2004. That's the equivalent of taking 10 million trips to the moon.
5 - Percent U.S. population is of the world population.
30 - Percent of world's automobiles in the United States.
45 - Percent that the United States contributes to the world's automotive carbon dioxide emissions.
4 - Number of car companies that support a national cap on global warming emissions. They are Ford, General Motors, DaimlerChrysler and Toyota.
0 - Number of bills passed by Congress to cut global warming pollution.
Tell Congress to do something about fuel economy.