26. The system according to claim 20 , wherein the description of online activities includes a description of which Web page was visited on the Web site.
20. A computer system for online re-targeted advertisement selection, comprising: a storage device configured to store advertising content associated with a Web site; a communications device configured to communicate with the Web site and a user; and an advertisement server configured to: receive a description of online activities for a collection of online identities for users accessing one or more affiliate web sites; identify a desired behavior, the desired behavior describing user interaction that indicates that an online identity demonstrating the desired behavior is more likely to be responsive to a re-targeted advertisement; analyze the description of online activities to determine whether a particular online identity appearing in the description of the online activities demonstrates the desired behavior; generate a watch list of users to receive re-targeted advertisements based on analyzing the description of online activities; monitor, in real-time and from the one or more affiliate web sites, information related to user interaction with the one or more affiliate web sites; receive, from within the monitored information, a request to display advertising content to a user; determine that the user appears in the watch list of users to receive re-targeted advertisements; and select, in response to the request, advertising content for display based upon determining that the user appears in the watch list of users to receive re-targeted advertisements.