Not a lot.  A lot of people call me Q, including several RL friends.  That got started and just sort of stuck.  One chick used to call me Monkey (because I often go by Mikey, and I had a lot of monkey crap people used to give me... stuffed animals and wind-up king kongs, whatever), but she didn't use it too much.  So... mostly just Q.  Which I respond to probably more quickly than my own name, since half the people who call me by my real name are people I can't stand, when almost everyone who calls me Q is in my good books.