52186 Announcement Script

I need a simple announcement script. The announcement page is like a guestbook. New annoucements are posted chronologically like a guestbook with timestamp. An email is sent out whenever that page is updated with a new announcement. Admin section includes ability to create new announcement pages, add/delete/modify email list,edit announcements. Also admin section allows to create users that can create announcements for either all or some of the different annoucement categories. When a user wants to sign up to receive notifications, they will go to a page that has a selection of all the annoucement page categories and they will check which ones they want to receive an email for. Also in the email, a link is sent that will allow a person to take themselves off a mailing list.