Facebook: it lets you find out way too much about your weird cousins, aids you in stalking your exes, and now, it helps the feds fight crime. In partnership with the FBI, Facebook assisted in nabbing a giant international crime ring that had been stealing the identities of people and doing $850 million in financial damage.
The FBI has arrested 10 people all over the world who had infected an astounding 11 million computers with "Yahos" malicious software to swipe credit card and bank data, as well as personal information. Facebook has been aiding the FBI since 2010, when Yahos first started victimizing its users using a butterfly botnet.
Image credits: Wikipedia