I've used Priceline for hotels and air fares and have always gotten good deals. Like the pp said, check out betterbidding.com first just to get yourself familier with how to use it. For airfare, I always check what the airlines are charging and go about 40% or so lower with my bid and usually get it. Just keep in mind that you have no control over the times of departure or arrival. They give you a spread of time but until you win the bid, you don't know what your times will be. If you have to be some place at a specific time, I wouldn't use Priceline. Good luck in your bidding.