Hacker groups that attack or steal
When they're angry, they hack into business and government systems to steal confidential data in order to expose information about their targets, or they simply disrupt them with denial-of-service attacks. These are the hackers with a cause, the "hacktivists" like the shadowy but well-publicized Anonymous or the short-lived Lulz Security group (which claimed to have just six members and just joined forces with Anonymous).

Over the years, Anonymous is believed to have hit targets that include the Church of Scientology, the Support Online Hip Hop website, the No Cussing Club website, and posted pornographic videos disguised as children's videos onto YouTube. It's said to have joined with Iranians protesting the results of the June 2009 Iranian presidential election. It's tied to taking down the Australian prime minister's website in 2009 because of the government's plans there to have ISPs censor porn on the Internet.