Had an argument with a guy once. He probably knows who I am. Might even recognise my name, it's hard to tell.
I don't really do much- I'll find myself posting like mad one day, then fading into silence for a good week or two, lurking, always lurking- so I don't think many people would be familiar with me.
That's the way I like it, though, because when I start to have a 'face' in a community, I'm tied to my set personality archetype. As it is, I can change who I am entirely without anyone noticing. Beauty of the Internet.