In an embodiment of a method of establishing a computer-based communication session involving a user of a computer, notification may be received from the user of a desired participant and a desired communications application for the session. A participant identifier effective to identify the desired participant to the desired communications application may then be retrieved, and the retrieved identifier may be provided to the communications application. An embodiment of a system for computer-based communications includes means for receiving notification of a desired participant in a communications session and a desired communications application for the session, means for retrieving a participant identifier appropriate to identify the desired participant to the desired communications application, and means for providing the retrieved participant identifier to the communications application. The means for receiving notification, means for retrieving a participant identifier and means for providing the identifier may include a communications aggregation program.