An apparatus and method for awarding prizes to equipment users during off-peak hours of an establishment. A plurality of machines, such as coin laundry washing machines or dryers, are all coupled through an activity interface to a master control unit. The master control unit comprises a timer, a counter,...http://www.google.ca/patents/US5217224?utm_source=gb-gplus-sharePatent US5217224 - Prize award system for coin laundry
