When I was in AF training people couldn't pronounce my first name Osvaldo, so one guy decided to call me by my initials O.O. Double O, and I ran with it every where I went. I've been flying a B-757/767 for over 16 years, so, when put together Double0757, nobody has that name in all the forums I belong to. To this day I'm known by Double O in all my social and work circles.
I don't have license to kill, but I'm working on it!