Oh my goodness ... those are all so cool! I thought about covering one with pennies or marbles but never have gotten around to it. I really love the one that you said someone walked off with and the one with the marbles is awesome, so colorful. I laughed out loud when I saw the one with the roofing nails, with the nails sticking out of only half, it looks like a punk hairdo!
Great job ... you are very creative!