United States Justice Department shut down the file upload site Megaupload on January 19, 2012. This also lead Anonymous, a famous hacktivist group, create a single largest internet attack in the history.
Anonymous planned on attacking Recording Industry Association of America, Motion Picture Association of America, and Broadcast Music Incorporated. This was thought the beginning of the postponed bill, Stop Online Piracy Act.
Sadly, I could not upload large file
Source : http://en.wikipedia.org/wiki/Megaupload#Retaliatory_attacks_by_.27Anonymous.27