How to monitor changes to an arbitrary web page, and subscribe to the changes via RSS.
I've seen services like this before, where you give a URL and you're given an RSS feed of changes to the web page.  But google is not turning up anything quite as simple/usable as what I'm remembering.

Please submit one such service or solution per answer so that as the landscape changes they can be voted up or down accordingly.

(Custom scripts and such are of course very welcome.)
How to monitor changes to an arbitrary web page, and subscribe to the changes via RSS.
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I've seen services like this before, where you give a URL and you're given an RSS feed of changes to the web page.  But google is not turning up anything quite as simple/usable as what I'm remembering.

Please submit one such service or solution per answer so that as the landscape changes they can be voted up or down accordingly.

(Custom scripts and such are of course very welcome.)