Generally, I do not feel that shaggy dogs involving invented words or names are of the highest quality, though clearly there are many of them. This example may not be venerable, but it is ancient.

A family owned a beautiful piano, but it needed tuning. They hear of a terrific piano tuner in town named Opporknockity. They call, he comes, and he tunes the piano quickly and precisely.

A year later, they decide to have it tuned again, and call Mr. Opporknockity. They tell him how happy they were with his last job, but he replies, “I’m sorry, but Opporknockity tunes but once.”