"I never really liked traditional monopods. What I have found to be very useful is what some people call a string monopod.

Here's how to make one version of this device.You need a 1/4x20 eyebolt, two 1/4x20 nuts, and a length of clothes line (or any line that doesn't stretch). Put both nuts on the eyebolt, and then carefully attach the eyebolt to the camera's tripod mount. If you over tighten the eyebolt you can damage the camera's bottom plate. Gently tighten one of the nuts against the camera's bottom plate, and then tighten the other nut against the first. The nuts will prevent you from over tightening the eyebolt when you re-attach the eyebolt later. Now you tie the rope to the eyebolt.

To use the string monopod attach it to the camera, drop the rope on the floor, step on it, and then pull up to put tension on the rope.

I've had very good luck with this. For last year's Solo Photo Book Month project, I shot on the streets of Manhattan with a handheld Yashica Mat 124G and a string monopod. I was able to use shutter speeds as low as 1/30 second.