OpenDNS has a whole bunch of other opt-out (per IP) features that depend on DNS-level hijacking. By default they point NXDOMAIN to their own landing page, blac

OpenDNS has a whole bunch of other opt-out (per IP) features that depend on DNS-level hijacking. By default they point NXDOMAIN to their own landing page, blacklist 'known phishing sites', and proxy some Google requests through their own servers to defeat clever browser address bars.