Your script, I assessed the options but the quickest way to get this online was using your script. So that's what I decided on.
I have thought about how to subscribe yourself to notifications and decided on a single token signup kind of thing.
So if you want to get alerts about one of the servers you fill in your email address you would like to receive the notifications on. A email will be send with a confirmation token, once you click the link and fill in the confirmation token you will start receiving emails. Every alert email will have an "unsubscribe" link to stop getting alerts.
I think I like this over full user accounts since this is probably something you will only do once and then forget about it, creating a whole new account for yet an other website seems silly. Ideas?