BoltMail
Is it possible for a user to ban his e-mail address? (A global unsubscribe for all our send-outs)
If you would like your users to be able to unsubscribe from all of your contact lists at the one time you can create an unsubscribe form that unsubscribes from all of your contact list and make the form available to them.

Other wise you can simply add an unsubscribe link into your emails as you send them allowing your contacts to unsubscribe as they receive your emails.