I've heard about package deals on the USAirways BOS-DCA shuttle -- I think this involved buying 3 tickets and getting the 4th free. Does anyone know if this package -- or *any* shuttle discount package -- still exists? I fly this route about twice a month to see family, often on short notice, and would love to take advantage of a deal. If there are no shuttle packages, any other suggestions on the best deals for this route?