I just read a story yesterday about a pilot who chopped his head off trying to hand-prop his plane. There were many terrible comments, one from a man laughing at his predicament and nominating the pilot for the Darwin Award and such, and mocking family and friends who were commenting to pay their respects.
The commenter's first, middle, and last name appeared right next to a picture of himself with his kids.
Google announced recently that it didn't. They thought it would, but it turns out that people are perfectly happy to behave awfully under their real name (or, in some cases, throwaway accounts).
Interesting - are Facebook users really better-behaved than average blog commenters? Or was it just that the lazier trolls gave up when their old cookies stopped working?
Look at sensationalist TV (eg, Jerry Springer or Jeremy Kyle or similar) to see people who are more than happy to have their real world identity tied to extremes of behaviour.