While they're back online now, for a while there, both the Motion Picture Association of America and Recording Industry Association of America's websites were under DDoS attacks from piracy-lovin' 4chan members.
What caused 4chan to focus its attention on these two sites? In the MPAA's case, it was after an Indian anti-piracy company's CEO boasted of attacks on The Pirate Bay and other torrent sites. The company, which kickstarted the ill-feelings between both sides (or just further elongated the animosity already felt), AiPlex Software, was taken down first for 18 long, long hours. We know how you feel, guys. [TorrentFreak via Defamer, Wired UK]