This one's not necessarily nautical in nature, but it's interesting.
Pulling Your Leg
Up until 1780, death by hanging in England was performed by slipping the noose around the condemned's neck and hauling them into the air. The neck was not broken as in modern practice. In order to speed the victim's passing, a friend or loved one would grab the condemned's legs and pull, adding their weight, quickening the strangulation process. It was the last act of compassion that could be given to the dying person.