For a while I used the handle 'duckstab', although I gave that up as too disturbing, although I still use it as the name for one of my computers. But it was one of those 'hey, if I use this, I'll be totally unique across the Internet'. Most likely. (The name comes from the Resident's EP 'Duck Stab' (or, these days, 'Duck Stab/Buster & Glen').)
So I was kind of surprised to find someone linking to a comment by someone on Metafilter, whose profile revealed them to have the handle 'duckstab' and the real name Sean. "Is this some account I created ages ago and forgot about? No, it appears to be active. What the?!?!"