Leave the SUV in the driveway. For vacationers this summer, it may be cheaper to fly than drive to many of the most popular getaway destinations in the U.S. Today, priceline.com released its “Frugal 15″ - a list of the 15 best airline ticket deals for those who book their summer 2007 travel now.

News on the gasoline front certainly isn’t promising.

According to the federal Energy Information Administration, the average price of a gallon of gas for the week of May 14, 2007, was $3.10. That’s already above last year’s peak and represents the highest per-gallon price in the last three years. In cities like San Francisco, the price has topped $3.50 a gallon.

Anyone planning to make the 1,706 mile round trip from Washington, DC, to Orlando in a 20-mpg Ford Explorer can expect to spend 26 hours behind the wheel and $267 in gasoline at the $3.10-a-gallon national average. By air, the trip would take a little over 2 hours each way and cost $123.

The Priceline Frugal 15 List

Quoted prices are round-trip coach and include all taxes and fees(a)

(a) Airfares shown are for round-trip travel and are inclusive of all taxes and fees. Fares shown are actual deals that were found and purchased by priceline.com customers between May 9, 2007 and May 15, 2007, for their summer travel. Airfares and availability are subject to change frequently and without notice, and there is no guarantee that any fare will be available. Prices for travel on other dates may be different.