So a piece of string walks into a bar, goes to the bartender and asks for a beer. The bar tender looks at him and says, "we don't serve pieces of string here. Hit the road jack!"
So the string leaves the bar and asks a man standing outside to tie him in a knot and fray him at both ends. He goes back inside and again asks the bartender for a beer. The bartender doesn't seem amused. "Aren't you that piece of string I just sent packing?"
The string replies, "no sir, I'm a frayed knot!"