The log was called like this by the guys at gibson that first saw Les paul coming at them with a bodyless guitar (looking a lot like the small plastic steinberger, the headless ones). They almost kicked him out of the factory, and kept making fun of his "log", Les finally had to screw body parts on the sides of the guitar so that people would agree that it played and sounded great. Actually, Gibson called back the "guy with the broomlike guitar" when the broadcaster (telecaster a little later) started selling good...