In front of a delicatessen, an art connoisseur noticed a mangy little kitten lapping up milk from a saucer. The saucer, he realized with a start, was a very rare and precious piece of pottery.
He strolled into the store and offered 20 dollars for the cat. "It's not for sale," said the proprietor.
"Look," said the collector, "that cat is dirty and probably half wild, but I'm eccentric. I like cats that way. I'll raise my offer to 100 dollars."
"It's a deal," said the proprietor, and pocketed money on the spot.
"For that sum I'm sure you won't mind throwing in the saucer," said the connoisseur. "The kitten seems so happy drinking from it."
"Nothing doing," said the proprietor firmly. "That's my lucky saucer. So far this week I've sold 15 cats."