I grabbed some scrap cushion foam and jute rope, then whipped up my little creation. I stacked two pieces of foam together and trimmed them with scissors to get an overall rounded form, this one being roughly six inches in diameter and about four inches high. The tomato mashing dibble was the perfect tool for creating a nice big hole in the center.
I wrapped one end of the rope (I used 36' of rope for this project) with some duct tape, and fed it thru the "doughnut" hole all the way around. When I reached the end of my rope (no pun), I simply made a little knot and tucked it up into the hole.