Priceline is a great way to access unused rooms through Name Your Own Price and Express Deals
Name your own price lets YOU dictate a price
Express Deals offers you a price at which you can buy the hotel
You buy a hotel based solely on neighbourhood, star level and dates
You find out the actual hotel once the reservation is made
Rooms a non-refundable once a reservation is made
Savings can be higher than 50% off rack rates in some situations