For some reason, the information age tends to make assholes want to go global. By, for instance, abusing a cat on camera and posting it on YouTube.
When a 14-year-old kid decided he'd post his own cat torture video, he probably didn't foresee the massive response he'd get once it spread across the Internet, leaving YouTube and heading to places like 4chan and other corners of Hell where the foolish are punished for their glaring webcam indiscretions. There, the denizens that some call "Internet detectives" and that we call "tentacle child porn enthusiasts" tracked the abuser down through his Facebook and MySpace accounts, because assholes are also generally not bright enough to not wallpaper the Internet with their own photos and personal information.
The result of Anonymous's detective work is that there appeared an entire website devoted to the teen, including his picture, links to the videos he made, the names of his parents, their addresses, phone number (as well as work addresses and numbers) and the website address of his father's business, which is now strangely absent from the Internet.
In a curious twist, the use of gay fan fiction also came into play, on websites that review the father's business, featuring such charming passages as "Tito was naked, standing in front of him with a big Hawaii boner staring him in the face. 'As the ancient Hawaiians used to say... it's time for a dicking!'"
The news media caught wind of the story, and then local police started getting inundated with calls from all around the world. Businesses in town got the same treatment including a number that weren't involved in any way due to the wrong information being spread online. Oddly, the police response to this was to politely ask people to stop as they might "stalk the wrong person."
The cat was taken out of the home. The abuser and his brother (also in the video) were charged by the local cops.
Debate rages to this day as to whether Anonymous went too far, since they tend to not apply this much righteous rage or sympathy to actual human beings. But then there is the case of Chris Forcand...