Users can't change their IDs on their own... just imagine the chaos that would happen if people went around changing their identities all the time.
There is a big enough problem with clones - people logging in under multiple identities. Of course anyone can create a clone by re-registering but inherently it is dishonest because you're deceiving the other members, so this is automatically labelled "uncool" and woe to the clone who is unmasked because the other members would really let 'em have it. Ask the old timers here and you'll get an earful of clone stories.
But if you really want to change your name for some reason, just drop me an email at
jim@tribiani.com explaining why you want this done, and what your current ID is. And I'll attend to it.