Create a copy of the notification subscription view html form on your local computer.
Set the id of the node / object tree root you want to subscribe, normally this is a low number like 2
Load your local html in a browser submit customized form for processing.
Success you have just subscribed to all notifications for the entire site, no need to ever subscribe to notifications on the site as you now already have a root content tree notification rule which since at the root of the site's content tree gives you notifications for all child content objects modified/added/etc.
I hope this helps. This trick lets me track all changes on projects.ez.no and share.ez.no sites via email notifications without having to actually watch the site for changes.
