Here is a quick present that I created over the weekend for someone. They wanted a large monkey fist to keep one of their doors ajar.
When I created this one I decided that it should have a long loop so that it could be hung over the door handle. The loop was just long enough so that the monkey fist would drag on the floor when the door was opened or shut. This way instead of opening the door the desired amount, then with your foot rolling the monkey fist into position, by being attached to the handle the fist would always follow the door.
The actual rope was some second hand stuff that I found dirt cheap at a car boot sale.