I recently came upon a situation where neither of my tripods would work for me. I need to shoot a group photo of up to 65 people in a small space. Thus, I need to get very high above the group. How do I support my camera nine feet above the floor? I found the solution. I bought a Bogen/Manfrotto 3424 Column Clamp and clamp it to a board that I screwed to the top of an 8-foot industrial stepladder that I own. Then I put the center column from my 3021BPro tripod into the Column Clamp and voila - I have an 8-foot quad-pod with about 18 inches of vertical adjustment with the column. Here are a couple pictures of the 3424 Column Clamp:
This clamp opens up to about two inches, and has notches inside the clamping surfaces so that it will work on boards, tree limbs, pipes, etc. It will even clamp to the lower leg of your tripod and get the camera very close to the ground.

