- “Feigenbaum! I have to find him. He's the master of- I have to have Feigenbaum here”
- ―Fred[src]
Feigenbaum is Winifred "Fred" Burkle's stuffed toy rabbit and known affectionately by her as "the master of chaos". He is named after Mitchell Jay Feigenbaum a mathematical physicist and pioneer in the studies of chaos theory. His only appearence is in A Hole in the World.