This blog has been migrated between platforms a few times, so I may have broken some links.

If you don’t mind, please log an issue with the URL you were trying to reach and where you found the URL. Thanks!

10.4.5 404 Not Found

The server has not found anything matching the Request-URI. No
indication is given of whether the condition is temporary or
permanent. The 410 (Gone) status code SHOULD be used if the server
knows, through some internally configurable mechanism, that an old
resource is permanently unavailable and has no forwarding
address. This status code is commonly used when the server does not
wish to reveal exactly why the request has been refused, or when no
other response is applicable.

(from RFC2616)