jCheck is a simple service to check for changes in webpages. Add a URL, choose a name for it and the checking interval (5 minutes, 1 hour, 1 day...). Everything is done on the server, so wherever you are jCheck will alert you (by email and/or by push notifications) whenever anything changes on that page. A snapshot of the page at the time the change was detected is also saved, so you can see how it changed over time and maybe see the last change if the site is down.

You can also access everything through the site: http://jota.pm/jCheck