WWW::WebArchive is a set of modules to retrieve old versions of public web pages
from various web archives.

* http://www.archive.org - Internet Archive's Wayback Machine
* http://www.google.com - Google's page cache

This is useful if

1. Your web server crashed and you didn't have complete backups
2. A site (such as a valuable reference source) changed or went away and you
  want to restore an old version of the site to your local disk
