A method for providing add-on services responsive to an email transferred via a distributed computer network. The method includes receiving via the distributed computer network the email at an add-on service system. The method further includes ascertaining from the email whether a recipient of the email subscribes to at least one of the add-on services. If the recipient subscribes to the at least one of the add-on services, the method includes forming a post add-on service email, which includes performing, using the add-on service system, the at least one of the add-on services on at least a first portion of the email. Furthermore, the method includes forwarding the post add-on service email, after the performing, to the email system, thereby rendering the post add-on service email accessible to the recipient through the email system.