01. Paranoid: The kind that prefer to be anonymous 100% of the time. Anti-Socialite.
02. Avatar: The kind that prefer to be anonymous but give tiny hints about themselves (avatars, location, age, sex, etc), which may lead to becoming very non-anonymous. Looking for Friends.
03. Open Book: The kind that tell you everything about them. They use their real name, they do things elsewhere that provide exact locations, etc. Desperate for recognition.
Freud said that everything we do can be traced back to two things, Fear and Sex, so:
01. Based on Fear.
02. Based on Sex.
03. Based on Fear and Sex.
In my opinion, we're all a bit crazy, but group 02 and 03 is the craziest.

And, my opinion about having or not having avatars, signatures, whatever is: Does it really matter? I thought it was just something you did after you have been at one place for like ever. I had no idea that people carried this "Second-Life" identity everywhere they go. Anyway, from the outside, it seems normal enough, so do what you want as long as the way you represent yourself isn't offensive, then it shouldn't matter to anyone else. It certainly doesn't to me at all. I say, if you're gonna do it, then do it all the way. Get your avatars trademarked, watermarked and ready for prime time. You need to find a good graphic artist and really get it right. You know, take your Second-Life to the next level. But, you have to first think that you're worth it. I think you're worth it.