Nah, I have a fake account because some websites have a Facebook integrated comments section. Yes, I do have an overriding need to throw out my 2 cents like every other self important prick on the internet, but I don't want spam in my regular inbox or identity thieves connecting the dots in my life, so sue me. If websites didn't use Facebook and had a more traditional comments system I'd still sign up with a pseudonym and a throwaway email address.
This need to identify yourself online, and the whole "you're a coward for not attaching your real life identity to what you say online" sentiment... Where does it come from? Old people who don't understand basic security measures online? AOLers who think they're in some safe walled garden? Actual retards?