Cut out a 1/2" piece of plywood to the dimension of your laptop. Give it an additional 1/2" all the way around.
     Mount the nipples and flanges to the flex pipe and screw it to the plywood using four 1/2" flat head screws. I would mount the flange near the back of the plywood base because most of the weight will be toward the back when the screen is raised up.

     Take the flex pipe off the flange and take it with you to the hardware store. Using elbows of different angles and pipes of different lengths build up an arrangement that matches your flex pipe shape. I used a coupling for connection to the top flange so that it will be easy to adjust and remove.

     I put an edge around the board to make it look nicer and help keep things in place. The last thing I did was screw it to the floor using four flat head screws and I put at non slip pad on top. It seems to hold the laptop well and is quite solid.
     For a final appearance I covered the galvanized pipe with pipe insulation. It actually doesn't look too bad and is quite functional.