Page2RSS is a very nice service that
creates feeds from any web page, by including the new content and
linking to a page that highlights the differences.
A simple
example of web page that could be monitored using Page2RSS is
google.com: a homepage that rarely changes only to celebrate important
events or to announce new Google features. You could subscribe to the
automatically-generated feed by visiting:
http://page2rss.com/page?url=www.google.com/. This also works for international sites like
Google Japan,
Google Italy etc. Unfortunately, you'll also receive an update when Google puts the classic logo back.

Of
course, the service is useful for any web page that doesn't offer
feeds, but it's better suited for web pages that don't change very
frequently since Page2RSS checks to see if there's new content every 4
hours. You could use it to generate feeds for changelogs, privacy
policies, news sites,
Google Labs or to find new features in Google's services, like Hindi support added to
Google Translate on April 29. Can you find other interesting web pages that could be monitored using Page2RSS?