I've used something very similar to the K&M side bar mic clamp on the stand accessories page at micsupply.com. Only thing I don't like about it is it needed a modification to fit on my light stand as the stand's shaft was too big for the clamp and I had to "massage" the opening abit to get it to fit. Other than that it has worked well (with the proper thread adapter) for mounting both still and video cameras.