rook

How to stop people circumventing your filter

So the ISPs have started blocking your secret blacklist by poisoning the DNS for all the domains in it. Since it's easy to use another DNS server, though, the ISPs have started discarding all traffic to to all IP addresses on the blacklist. Things seem to be going well for about six hours until a news story airs of a teenager using a proxy server to access some of the hideously violent and massively illegal material on the blacklist (for example, one of the several sites that were last year added to the blacklist for containing nudity).

from No Internet Censorship for Australia