There's been a slew of litigation in the online privacy space in the past few years—despite the fact there aren't many online privacy laws to sue over. But the lawsuits have come nonetheless, tackling privacy issues ranging from data breaches to "supercookies."
One of the most prominent cases was the Facebook lawsuit over "Sponsored Stories," in which users' pictures were used to endorse products they had "liked" without their permission and often without their knowledge. There was no opt-out, to boot.
A lawsuit was filed in California claiming Facebook's action violated the state's right-of-publicity law as well as an unfair competition law (which kind of gets thrown into many privacy suits). Perhaps realizing they were going to be on the wrong side of public opinion the case resolved, Facebook settled the lawsuit relatively quickly for slightly more than $20 million. (Sure, that's not a lot for Facebook, but that's actually on the high side of privacy lawsuit payouts.)