I stopped at a fast food restaurant recently. I was fascinated by a sign which offered fat free French fries.

I decided to give them a try. I was dismayed when the clerk pulled a basket of fries from the fryer which were dripping with fat. He filled a bag with these fries and put them in my order.

"Just a minute!" I said. 'Those aren't fat free."

"Yes, they are. We only charge for the potatoes.... The fat is free!"