Two Polacks were building a house.
One of them was on the roof. He picked up a nail, hammered it in. Picked up another nail, threw it away. Picked up a nail, hammered it in. Picked up another, threw it away.
This went on for quite a while. Until finally his friend looked up and asked, “Why are you throwing the nails away?”
“They were facing the wrong way,” he replied. “The pointy end was the wrong direction.”
“You idiot,” his buddy screamed, “Those were for the ceiling!”
