Some friends and I recently organized a trip to Las Vegas. We were able to find great hotel rates for Friday night, but published Saturday night rates were crazy expensive. So we turned to Priceline, and within minutes we had a 5-star hotel for Saturday, on the Strip, for a fraction of the lowest listed price. Priceline, Hotwire and vacation packages from offline and online travel agencies can offer prices that are dramatically lower than published rates without cannibalizing revenue because they are opaque selling channels.