#2 Government websites

Anonymous claimed responsibility for taking down government websites in the UK in April 2012 in protest against government extradition and surveillance policies. A message was left on Twitter saying it was "for your draconian surveillance proposals."

#1 Revealing Chinese Hand In Cyber Attacks On U.S.

Anonymous released user information from a major hacking forum in February 2011, and security firm Mandiant was able to use this data to link the Chinese military to cyber-attacks against the U.S. this year.

Bonus:

Raising Voice For Freedom Of North Korea

Earlier this month, Anonymous began "Operation Free Korea." It’s an effort by the hactivist group to oust controversial leader Kim Jong-un and install free democracy, abandon nuclear ambition, and grant uncensored internet access to its citizens. On April 3, Anonymous released all 15,000 usernames and passwords for the government's web services and threatened to wipe its data.

The Steubenville Rape Case

The Steubenville Rape Case, the images of the high school victim were disseminated on social media. To retort such senselessness, Anonymous released incriminating video, tweets, and emails belonging to accused players on the school's football team.

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