If you’re making a “mattress run” for points, this Web site might help. TripAdvisor has added a new tool to its Web site that will help vacationers find travel destinations that can be reached with one tank of gas or less. The Gas Tank Getaways tool allows users to type in a city and search for destinations a quarter of a tank, a half tank or a full tank away. TripAdvisor will display up to five suggested destinations, based on traveler ratings. For each destination, you’ll find a list of three of the top-rated attractions and a link to take you to more attractions, restaurants and hotels. The site will also display the distance between your starting point and the destination and the estimated fuel cost. Go to www.tripadvisor.com/tankofgas