MINI Cooper
After BMW bought the MINI brand in 2001, the car has grown in popularity in the U.S., partially due to its marketing efforts: "During the production of first generation Mini, as a joke and undoubtedly as a part of Mini's viral marketing approach, purchasers of the Mini convertible were asked to sign a "contract" promising that they would drive the car with the roof open at least 90% of the time. Mini also set up a telephone hotline (in the USA: 1-888-DO NOT CLOSE) which one may call to report convertible owners who are driving with the roof up inappropriately. The automated system offers such helpful advice as how to administer a wedgie to the offender."
Read Paul Knight's Prius feature: "Wild Rides."