A guy walks into a bar with a monkey on his shoulder and sits down at the bar.
The monkey jumps down off the guy's shoulder and runs down to the end of the bar, hops on the pool table, grabs the cue ball and eats it. The bar tender exclaims, "hey, I need that cue ball for the table, what the hell man?"
The owner of the monkey says "what can I do? When the monkey passes it I'll clean it up and bring it back to you." The bartender says "fine".

The next day, the guy with the monkey returns. He walks in and tosses the cue ball to the bartender.
Again the guy sits down at the bar and again the >monkey jumps down off his shoulder and runs down to the end of the bar, this time to a bowl of peanuts. The monkey grabs a peanut, shoves it up his ass, pulls it out and eats it.
To which the bartender asks "What the hell is that monkey doing now?" The guy replies: " after that cue ball incident he sizes everything!"