System and a method for facilitating the use of a preferred, discount rate pre-paid telephone calling card. The system and method include and involved a data storage system for storing data corresponding to a pre-paid telephone calling card and at least one location identifier related to the pre-paid...http://www.google.de/patents/US6404869?utm_source=gb-gplus-sharePatent US6404869 - Preferred billing rate pre-paid telephone calling card
