Little black dog named Delilah. An employee of mine started calling her Doodle. Eventually her name became Dude.
Cat named Forklift. Little kids in our apartment building thought the name was Forked Lips. Cat ended up being called Lips.
I suppose the Forklift part is as odd as any of that. I had friend named Bridge. We joked that he had a brother named Bill, short for Building. Then we joked about other odd names, and eventually I ended up calling the cat one of those names.