Clark is often way ahead of the curve when it comes to money-saving vehicles.

Decades ago, he got a 3-wheeled car called the Freeway that got 100 mpg. Recently he read that an automaker named ZAP has teamed with the state of Kentucky to make an electric 3-wheeled car. The ZAP will go 40 mph and cost about 2 cents/mile to operate.

About 8 years ago, Clark bought his first hybrid -- a Honda Insight. Today, another hybrid called the Prius is in such demand that even 2-year-old models with 30,000 miles are selling for the manufacturer's suggested retail price.

Last year, Clark got the Honda Civic GX -- a natural-gas vehicle. Now comes word that his new ride is the hardest car to get in the United States!

That puts Clark in a dilemma: Should he capitalize on the situation and sell his Honda Civic for more than he paid for it? Or should he keep it and continue to enjoy the tremendous fuel savings? What would a capitalist do? He'll have to run the numbers and get back to you!