Heaving Line Noose Knot: This is a rather clever little way of adding weight to the end of a rope. However, not only weight but also a Noose Knot, and a Slip Knot. If you throw this line and the knots gets jammed, just a quick tug will cause it to undo and you retrieve your rope without snagging. So #LetsGetKnotting :

How to Tie a Non Jamming Heaving Line Knot