Tornado.

Coren:  "Mom there is a tornado on my finger."

Mom:  "What do you mean?"

Coren:  "It is a tornado you know, it is going around and 

               around."

Coren:  "Wait, there is one on my toe too!"

Mom:  "When we get out of the car I will take a look, I am not

               sure what you mean."

Coren:  "I am going to scratch it off."