The present invention discloses a voucher-based gaming transaction system, wherein vouchers are used for game credits rather than any form of coins or bills. Further disclosed are gaming machines that have the ability to fully transact using vouchers, including the ability to read, write, encrypt, and...http://www.google.ca/patents/US6652380?utm_source=gb-gplus-sharePatent US6652380 - Cashless gaming system and method
