This will be a very easy thread for me to contribute to as I've mentioned before, one of my co-workers is the master of malapropisms and can be counted on to entertain us with a different one at least once a week. She in fact is the sayer of the best one in the history of the universe - the one you mentioned, Sudz.
But before I share a couple of real ones, may I tell my very favorite joke in the whole world, based on a misunderstanding?
The little girl had gone to the barber shop with her grandpa to keep him company while he got a haircut. As the barber worked she stood close to grandpa, eating a muffin he bought her on the way. As the clippers flew over the grandpa's head, tiny pieces of gray hair floating around the three of them. Seeing this the barber warned the little girl: "Honey, you're going to get hair on your muffin." To which the little girl replied: "I know. Mommy says I'm gonna get boobies, too."
What a precious tale.
So, back to real-life malaprops:
My best friend, talking about the natural body chemicals that get her high when she exercises: "They endomorphins were just racing through my body."
My co-worker, discussing how cold her husband was at the Mardi Gras parade. "I tried to tell him he needed ear muffins."
Same co-worker, sharing details of her Valentine's date with her husband "He had turf and tail."
R, talking about a friend who always complained about imaginary illnesses: "He's psychoschematic."
Co-worker, discussing the various countries represented at Branson: "There were Italians and Spaniards and Uraniums..."
I have so many more. In fact, we have a book here at work showcasing our employee's endearing comments over the years. It's eight typed pages long. I work with doofuses. God love'em.
-frolix