Entire subreddits -- iamverysmart and similar -- which are devoted to finding people who made a comment which was embarrassing in some way, and publicizing it widely. One day, half of the videos on the front page of reddit (default page when not logged in) were random cell phone and surveillance footage -- people who don't know they were being filmed -- doing something dumb or being jerks.
Now, those people were genuinely jerks, but we've all been jerks at some point in our lives. Should that really become an internet phenomenon that will track those people for the rest of their lives?
We've got the political mobs too (the liberal mob and its feminist sub-mob tend to be particularly aggressive in ripping people apart, with similar but smaller communities on the right).