Some people have been sharing this idea but it doesn't really work. The idea is to create the affect of a monopod with just a string and some metal rings, thereby reducing the weight of your camera bag. First how does it work? Take a couple of washers and tie them to one end of some twine. Take the other end of the twine and attach it to the tripod mount at the bottom of your camera. Let the washers drop to the ground and put your foot on it. Pull the camera up against the twine. The theory is that by doing so you will be able to steady your camera because you have opposing forces. Unfortunately this doesn't work.
If you need a monopod, then buy one. Please view this blog for more information on how to shop for a monopod. Buying a Monopod