A string walks into a bar...

...and asks the bartender for a beer.
He nods toward a sign that says "We don't serve strings!". The string leaves and puts on a hat and walks back in. He tries to order a beer. The bartender goes to get one but looks at him suspiciously and asks "Are you a string?". The string says yes and leaves dejectedly. He makes one more effort and sneaks in through the bank door and goes into the bathroom. He ties the end of himself into a knot and frays the edges to look like hair. He goes to the bar and the bartender asks him...."Are you a string?"
The string replies....
"No, I'm a frayed knot!"