Automatic Mailing Lists 

E-Mail->MailingLists->Automatic

Automatic mailing lists are just like normal mailing lists, except that you can subscribe and unsubscribe to them automatically as well as manually.

Subscribing to automatic mailing lists
Send an e-mail to the e-mail address "list-server@domain" with the subject line "subscribe<space>mailing-list-name". The body is irrelevant and will be ignored.

Unsubscribing from automatic mailing lists
Send an e-mail to the e-mail address "list-server@domain" with the subject line "unsubscribe<space>mailing-list-name". The body is irrelevant and will be ignored.