This is the prefect Firefox add-on for the dreaded 404 message, or if you want to see which version of a page the search engines have in their cache. You can try five page cache/mirrors in turn: CoralCDN, Google Cache, Yahoo! Cache, The Internet Archive and the MSN/Live Cache. The search engine caches usually only have copies going back days or, at most, weeks but the Internet Archive may have copies going back to 1996. If you have installed Firefox 2 you may need to use the Nightly Tester Tool add-on to persuade Firefox that Resurrect Pages is compatible.