I prefer OpenDNS, but this might be useful otherwise.

Transparent Software Update Server! If I could get away with taking down the network for a little bit, this would be awesome to implement.

Using OpenDNS for now, but if that ever changes, that might be handy.

"Francisco Amato of Infobyte Security Research just announced ISR-evilgrade v1.0.0, a toolkit for exploiting products which perform online updates in an insecure fashion."