I've seen folks using elevated GoPro camera mounts on the front or back of their kayaks to get a nice perspective of whitewater action. A kayak company sells a nice one for the entirely too high prices of $150. Here's how to make one on the cheap.
Step 1: Go to Walmart, Buy a Toilet Plunger for 2.89
Select a plunger with just the classic shape and no "power cone" or whatever underneath the basic flange.
Step 2: Find a Regular Stick on GoPro Mount and Scrounge Around for Some Plastic and Screws
As you can see here, the top of the mount is stuck on a piece of plastic and then the plastic is screwed to the plunger at the top. I used a fillet of Goop on the back sides of the plastic and plunger just to stabilize things.
Before I mounted the GoPro to the plastic, I sanded the plastic and then stood on the mount after sticking it on to really stick it on.
Step 3: Drill Holes in Your Plunger
Face the front of the GoPro mount on the top of the plunger and then drill holes in front and then at 90 degree increments so that you can run a string around a grab loop that runs either front to back or side to side. The holes should be big enough that you can easily thread the string through.
The hammer here is a substitute for a grab loop.
Step 4: Drill Holes in the Shaft and Route Your String.
Drill one smaller hole the same diameter of the string front to back in your handle. Thread the string through and knot it off.
Drill three larger holes that are easy to thread higher up on your plunger. Run the string down through the holes in the rubber, around your grab loop, back through the rubber and then weave through the three holes which create a friction mount so that you can pull it tight. Secure with a hitch at the top.
Step 5: Mount to Your Kayak and Have Fun.
Ok, mount the plunger to your kayak with some string. Take awesome video of your carnage and fails. Post to youtube.
I would suggest a secondary safety line of monofilament or whatever in case there is some failure. The plunger might take a beating if you get rolled.