Haha, I think most people don't understand it!
It's from a movie with James McAvoy.

In the movie there is a male writer who writes stories that are for women and he doesn't want to be known as being the author. So he thinks "I need a pseudonym... I need a pseudonym!" and then he has the idea to call himself "Sue De Nimes" because it sounds exactly the same (ok, depending on how you pronounce it).
I've seen that scene and knew that's my name, I think it's a great word play hahaha