The only way i can think of doing it is to collect the default page, and then harvest all urls pointing to a similar depth page on the same url. Get the information for all of this (modification date, size etc), and check them against the original. For this to work you need the page to have a link to itself that actually specifies a file. so <a href=http://www.google.com/">main page won't help but <a href=http://www.google.com/index.html">main page will. Of course with mod_rewrite, and all the other .htaccess hacks the initial page could be dynamically created and only exists when provided, and not at all on the server!