Diff-IE is a prototype Add-on from Microsoft Research for Internet Explorer, that highlights the changes to a webpage since the last time you visited it and enables you to view and compare previously cached versions of the page.
Web pages change in a variety of ways. When changes are made obvious, especially the subtle and unexpected ones, you get a whole lot more out of the web pages you visit
Once you download and install this add-on, as you browse the web, you will start to notice how pages change. Since these changes are only tracked after you install Diff-IE, it may take a vist or two for these to show up on your favorite web site.
Through the Settings, you can also choose to ignore certain sites, change highlighting color, cache options, number of versions to cache and so on.
Diff IE: FAQ | Download page.