Not sure what else to call it...

I'm looking for some kind of script that will check if a domain has propagated, such as when a website moves from one server to another... and, if possible, sends some kind of warning, like an email or sms.

Basically, I want to be informed the moment a domain's dns has propagated.

I seem to recall seeing something like this. I believe it ran like a command terminal from the desktop and it would just keep pinging the domain.

Does something like this exist?

Keep in mind, propogation is not global, it can vary from ISP to ISP. My ISP might propogate in 2 minutes, while yours might take 2 hours, or 2 days.

oh, absolutely... I'm aware of that
Ofcourse it will also depend on the registrar as well

Well, you could use the dig command, but I don't know how you'd get it to text/page your phone.