http://www.bbc.co.uk/news/technology-16642369 After MegaUpload was taken down by US feds, the internet group Anonymous responded by taking down the US Department of Justice website, as well as several other record label companies.
"In one of the U.S. government's largest anti-piracy crackdowns ever, federal agents on Thursday arrested the leaders of and shut down Megaupload.com, a popular hub for illegal media downloads.
Hours later, Megaupload's fans turned the table on the feds. "Hacktivist" collective Anonymous said it set its sights on the U.S. Department of Justice and apparently knocked the agency's website offline.
"We are having website problems, but we're not sure what it's from," a DOJ spokeswoman told CNNMoney.
The DOJ website glitches came soon after various Twitter accounts associated with Anonymous took aim at the agency.
Anonymous's favorite weapon for these attacks is what's called a "distributed denial of service" (DDoS) attack, which directs a flood of traffic to a website and temporarily crashes it by overwhelming its servers. It doesn't actually involve any hacking or security breaches.
"One thing is certain: EXPECT US! #Megaupload" read one tweet from AnonOps that went out mid-afternoon.
One hour later, the same account tweeted a victory message: "Tango down!
http://universalmusic.com &
http://www.justice.gov// #Megaupload"
It was the largest attack ever by Anonymous, according to an Anonymous representative, with 5,635 people using a networking tool called a "low orbit ion cannon." A LOIC is software tool that aims a massive flood of traffic at a targeted site."
Full article here
http://money.cnn.com/2012/01/19/technology/megaupload_shutdown/