Moodle Plugins directory: Contributor: David Binney | Moodle.org

Allows staff and students to see enrolments they have in external systems (or other Moodle's). This was predominately created to allow links between archived and separated instances of Moodle, but keep the separation hidden to the users. Handy if you also have single-sign on between the systems, as it allows them to jump to external courses without having to login again.