Porsche's racing heritage and supreme level of luxury are well known. But what you may not know is some of their sports cars are easy on the gas as well. A 255-horsepower, 2.9-liter engine propels the Boxster from 0 to 60 miles per hour (0 to 96.6 kilometers per hour) in just 5.4 seconds. And with the seven-speed automatic transmission it gets 22 miles per gallon (9.4 kilometers per liter) city and 32 miles per gallon (13.6 kilometers per liter) highway. If you go with the sportier Boxster S model, the 0 to 60 miles per hour (0 to 96.6 kilometers per hour) time drops to 4.7 seconds and you'll still get 21 miles per gallon (8.9 kilometers per liter) in the city and 30 miles per gallon (12.8 kilometers per liter) on the highway.