404 (PAGE NOT FOUND)
This is an error page . . . but what if this error page was also an opportunity?
the web page you seek
cannot be located but
endless others exist
This page has been moved.
I’d tell you where, but then I’d
have to delete you.
TECHNICAL INFORMATION THAT IS ABSOLUTELY UNNECESSARY
Some proxy servers generate a 404 error when the remote host is not present, rather than returning the correct 500-range code when errors such as hostname resolution failures or refused TCP connections prevent the proxy server from satisfying the request. This can confuse programs that expect and act on specific responses, as they can no longer easily distinguish between an absent web server and a missing web page on a web server that is present.
In July 2004, the UK telecom provider BT Group deployed the Cleanfeed content blocking system, which returns a 404 error to any request for content identified as potentially illegal by the Internet Watch Foundation.
Other ISPs return a HTTP 403 "forbidden" error in the same circumstances. The practice of employing fake 404 errors as a means to conceal censorship has also been reported in Thailand and Tunisia. In Tunisia, where censorship is reportedly severe, people have become aware of the nature of the fake 404 errors and have created an imaginary character named "Ammar 404" who represents "the invisible censor"
During the May 2011 Greek protests, one of the most popular slogans was 'Error 404: Democracy not found'.