Page changes

A long time ago before blogs, I used to use a service called netmind that would monitor a webpage for change and send you an email when it changed. This was a handy way of checking pages such as a release log for a utility that didn't have its own mailing list etc. They then shut down and another service called spyonit did the same thing - again they shutdown (or you had to pay for it). This morning I discovered pagedetection which does the same thing. The blurb mentions that you can add a "subscribe now" type link in the page so users can sign up to be told when your page changes, but you can also add pages of your own choosing as a user too. Not much use on a blog (after all thats what RSS is for) but handy for pages that don't change often or don't have an rss feed.
I know you could use livebookmarks in firefox but in my short play with firefox I didn't discover a way of notifying me the page had changed.