When outlining, I sometimes have ideas faster than I can get them all down and I may not always have the new character names defined. I typically just use filler names until I feel the character out well enough to name him or her.
I enjoy running across these names in my outlines.
Here’s an example I found this morning.
Tom finds Col What'shisnuts
I guess I forgot to go back and fill in this name!
Poor Col. What’shisnuts doesn’t last long anyway.