I have a floating rail that a friend of mine made and then left me with when he went to Atlanta. It is 10 feet tall and filled with expanded foam. I have seen it float before, but I've never seen anyone hit it. I would predict that it will cause great bodily harm to anyone that takes it, so you'll have to release me of any liability when you take it (for free). We are in downtown GR near the Grand Valley campus, PM me if you want it and you can come pick it up.
It looks like it could be nice if you put some work into it, like adding skirts and perhaps a trex top instead of the PVC that is on it currently.