To the best of my knowledge, usernames can only be changed by someone with access to the board's database. I doubt this would be possible even in the extremest of cases because the easiest way to change a username is to simply make another.
yeah flubber, i would just create a new usename, and start over. dont worry about a couple hundred post, youll be back up there in no time. just do what some of these other dipshits do, just give every thread a bump once.