We need a email registration and management system. Where users can register with us by filling out a registration form that will look like a yahoo mail form or something like that. The form should have the option to opt in or out with opt in checked. The email registration should also generate a link that has to be visited by the user to agree to the registration again. The registration form should also capture the users IP address.
The admin should have the option to send everyone who is opt in an email or a newsletter. Each email should have a link at the bottom which, if clicked, should change the user's setting from opt in to opt out.