Google Tool Suggestion

I know I'm not the only one who's had this problem: you follow a link, or select an old bookmark for a site, and come up with a 404 error from the server. If you're "lucky", you'll be redirected to the site's main page, If you're really lucky, you may be redirected to the site's internal search engine. Common occurrence, right? Often happens after a major site redesign.

The problem is that you often don't know (or can't remember) enough about the page's content to form a useful query. Even if you can, many sites' search engines are terrible.

So--when (re)designing a site: archive the entire old site. Now, it would be possible to simply make the old pages available with a warning that they are outdated, but this might be undesirable for many reasons.

So--keep an archive of the past site's structure and content, and when a request for an outdated page comes along, run a comparison of that page (which is available only to the server) and find the best current match. Offer this to the user with an explanation. This makes the unavailable information useful, at zero cost to the user. Best of all, it doesn't require an explicit mapping of old URLs to new URLs. A "correct" match should be easily accomplished in most cases, although I don't have the algorithmic expertise to properly say. This also improves upon the Google cache solution by aligning the user with the new site paradigm, rather than just presenting the old information (which can be useful as well, for different needs).

Note to Google: my services are available for a reasonable fee.