Through Sept. 15, 2009, you can get double miles (100 miles) each way with any SuperShuttle airline partner including Delta SkyMiles, Frontier EarlyReturns, Northwest WorldPerks, United Mileage Plus and US Airways Dividend Miles. You can also save on your family vacation because also through Sept. 15, additional passengers ride for just $5. The additional passengers must be booked on the same reservation as the first passenger and from the same address and only one passenger can earn the miles. The $5 ride is limited to six additional passengers for residential shared-ride service only. This promotion is not valid in Miami, West Palm Beach or Houston.