A word of caution though. You build this, you take your camera's health into your own hands. I am not responsible should your camera fall and break or should this design slip causing your camera to plummet to the ground. In short, you are on your own!
And by all means, if you have a better idea for the design, please share it. This is a great community and we learn a lot. Now, let's get to work.
Step 1: Parts List ...
* 1 - 3/4" PVC pipe approx. 30" long. Note - Schedule 40 will NOT work for this. You need the thinner one - known as "eggshell." It's Schedule 20, IIRC. You need this one because the gray sprinkler pipe nipple will slide right inside it with little wiggle room.
* 1 - 36" x 1/2" PVC sprinkler riser pipe. These are the gray ones which you put the sprinkler head on.
* 1 - 1/4" by 3/4" hex bolt
* 2 - 1/4" flat washers
* 1 - 1/2" end caps
* 1 - 3/4" end cap - preferably a flat one
* 1 - 34" schedule 4 plug
* 1 - Handle replacement spring clip for pool skimmer head
* 1 - 3/4" foam pipe insulation
* 1 - Duct tape
Step 2: Preparing the Pipes
You'll also be cutting off one of the nipples on the 36" riser and drilling a 1/4" hole about a 1/2" down from the end. Router out a channel down to the hole and slip in the spring clip.
Wrap duct tape around the middle of the riser for about 10-12" long. This will serve to create friction as you slide the monopod up and down to adjust.
Step 3: Drill the Cap
Step 4: Paint Your Plastic
I used plastic primer white and then gloss black for this step. Note - I had these already in the garage so did not include this in the total. If you have to purchase these, then it'll push your total cost to $15 or more. YMMV.
Step 5: Putting It Together
Then, place the hex bolt and flat washer into the endcap hole and secure with a nut. Slip over the end of the monopod and you are done!
UPDATE: Did an adjustment to the monopod design. The V Clip just wasn't taking as much weight as I'd like, especially over time as the nub wears. So I replaced it with a home made PVC Clip designed and printed on a 3D printer by my friends at Mechanical Mashup. It's an ideal design and works perfectly.