Gaming system and method for providing a bonus based on number of gaming machines being actively played

A gaming system includes a controller linked to a plurality of gaming devices. The central server tracks: (i) a quantity of gaming devices being actively played by players, or (ii) a quantity of players actively playing at the gaming devices. The controller determines the players' eligibility for different awards based on the tracked quantity. When the controller tracks a first quantity, the controller provides the active players with an opportunity to win a first award. When the central server tracks a second quantity, the central server provides the active players with an opportunity to win a second award. As the tracked quantity changes, the controller determines or modifies the number of awards available to the players actively playing at the gaming devices.