These two Polish guys rent a boat and go fishing in a lake. They are amazed at the number of fish that they caught that day, so one says to the other, "We'll have to come back here tomorrow!"
The other asks, "But how will we remember where this spot is?"
The first guy then takes a can of spray paint, paints an X on the bottom of the boat, and says, "We'll just look for this X tomorrow."
The other guy says, "You idiot! How do you know we'll get the same boat?"