Writer's Block: Almost Famous

What celebrity do you think looks like you? What celebrity do other people say you look like?

Valerie Bertinelli (ex Mrs Eddie Van Halen)

How important is a user name?

I have used various user names on different forums though I generally stick to one.  However, the one I wanted here wasn't available and I couldn't think of anything else, so I just used my name.

Is your user name one you've used all over the internet or do you have different ones depending on the forum/site you're using?