1. A method for operating a client to retrieve desired content, said method comprising: checking availability of said desired content from other clients on a peer-to-peer network; if said content is available from at least one of said other clients, retrieving said content from at least one of said other clients via said peer-to-peer network; and if said content is not available from at least one of said other clients, retrieving said content from a content server of said peer-to-peer network.