1. A method, comprising: intercepting a session initiation protocol message used to initiate a bidirectional communication, the session initiation protocol message in transit to a networked recipient computer that provides interactive services for the bidirectional communication to be initiated; obtaining, based on information in the session initiation protocol message, supplemental information to provide to the networked recipient computer of the bidirectional communication to be initiated; inserting, using a computer processor of an intermediary computer, the supplemental information into the session initiation protocol message; and routing the session initiation protocol message with the supplemental information inserted to the networked recipient computer that provides the interactive services for the bidirectional communication to be initiated, wherein the session initiation protocol message is intercepted in a telecommunication provider network, supplemented in a session initiation protocol enrichment sub-system, and returned to the telecommunication provider network before reaching the networked recipient computer that provides the interactive services, wherein the session initiation protocol enrichment sub-system includes a rule engine that uses predetermined rules to determine what supplemental information to insert into the session initiation protocol message, and wherein the interactive services are provided based at least in part on the supplemental information.