Seven, probably eight years ago, when I moved from living with my mom to my dad, we got our internet connection from AOL, had to come up with a username for an email, was pretty stupid. But anyways, the two of us spent like an hour trying to come up with something not completely stupid or ugly. Eventually he made the suggestion to having something relating to me being such a gamer, giving things like "Nintendofreak" and other similar names. Which I really, really didn't like. Well, after pondering over names for a while longer I eventually settled down and, although not particularily fond of it, went with An64fan, which was an available username. Grew to love it, and have had it as my main username ever since.
Have a few alternate names I've used over the years, as well.
-Eska (What can I say, it's my name)
-Chais (was the name of my fav. chao on SA2B)
-Skyreal (Second main-level name, use it frequently, derived from the name of my first major Naruto OC, Skyreal Mokuro)
-Mokuro or MokuroS (Again, derived from my OC, though this is just a few miscellaneous cases)
-Akehoshi (translate the meaning of my real name into Japanese, and you get this. Third main-level name. Also happen to have an OC with the same name, no immediate relation though)
-LyzaraKitsune (my Youtube username. Had been playing MapleStory at the time, and came up with it there)
-Houkou-NRL (my deviantART username. The houkou is a mythical five-tailed dog in Japan. Love Japanese mythology. Favorite band happens to be No Regret Life. Tagged the two together, viola!)