Many hotels offer bonuses for staying at their properties and most require registering for the bonus even if you are already a member of their loyalty program.  A mattress run describes the process of staying in a specific hotel just to qualify for a specific bonus. It can be very worth while. Most of the deals can be found here  e.g. One of the best mattress run promos I’ve benefited from is

read more: Travel Hacking - Tip #11 – Mattress Runs - Hotel Promotions