So you want to have fun behind the wheel, but you worry sports cars aren't great on gas. Fear not: We've assembled a list of 10 fun cars for 2008 with low annual fuel costs. We started with the EPA's annual fuel-cost ratings, which reflect the current national average gas price and assume 15,000 miles divided between 55 percent city and 45 percent highway. We picked the highest-mileage transmission choice available in a given car. When annual fuel cost was the same, we looked for a net gain between city and highway efficiency, and ultimately used our star ratings – a quick look at our opinion on each vehicle – as a tiebreaker.