GNU Mailman
Setup
The Debian Wiki has a section on using GNU Mailman with Postfix.
From a random text file I had lying around on my disk:
## mailman mailing list mailman: "|/var/lib/mailman/mail/mailman post mailman" mailman-admin: "|/var/lib/mailman/mail/mailman admin mailman" mailman-bounces: "|/var/lib/mailman/mail/mailman bounces mailman" mailman-confirm: "|/var/lib/mailman/mail/mailman confirm mailman" mailman-join: "|/var/lib/mailman/mail/mailman join mailman" mailman-leave: "|/var/lib/mailman/mail/mailman leave mailman" mailman-owner: "|/var/lib/mailman/mail/mailman owner mailman" mailman-request: "|/var/lib/mailman/mail/mailman request mailman" mailman-subscribe: "|/var/lib/mailman/mail/mailman subscribe mailman" mailman-unsubscribe: "|/var/lib/mailman/mail/mailman unsubscribe mailman"
Moving lists
How do I move a list to a different server/Mailman installation?