I like being able to change it, it may confuse some but it's an option I'm happy exists.

I was Stella_Blue - - now I am - Box_of_Rain - - both Grateful Dead songs so I figured it wouldn't be too tough - and I included that in my signature.
Stella Blue identified me too much so I ditched it.
I was all kinds of befuddled when Legitimate changed her screen name though [duh]