Polaks Building A House

These two Polaks are building a house. One of them is putting on the siding. He picks up a nail, hammers it in. Picks up another nail, throws it away. Picks up a nail, hammers it in. Picks up another, throws it away. This goes on for a while, and finally his friend comes over and asks him why he is throwing half of the nails away.

He replies:

- Those ones were pointed on the wrong end.

The buddy gets exasperated and says...:

- You idiot, those are for the other side of the house!