A DIY blank extension, so you can later modify it to fit your needs without dealing with locally installed extensions.
Just place a tag in your template and you will be able to let users subscribe to your newsletter. The extension sends a verifying email so your "records" are not "published" until the verifying link is followed.
It lets you protect pages using a table in an external database to check for granted users. You can also set a master username and password to bypass database checking. Sorry... right now it only works with MySQL databases.