submitted by Pat F.
A duck walks into a bar and asks the bartender for corn. The bartender says "We have no corn, get out of here." So the duck leaves.
The next day he comes back and asks for corn again, and the bartender says "I told you, we don't have corn. Get out." So the duck leaves. The next day he goes in again and asks for corn and the bartender says, "For the last time, we don't have corn. If you ever come back, I'm going to nail those webbed feet of yours to the floor." So the duck leaves.
The next day the duck comes and asks, "Do you have any nails?" The bartender says, "No, of course not. Why would we have nails?" The duck then says, "Good. Then can I have some corn?"