How about this: Nail his scrotum to the top of a telephone pole. Then pour hot lead in his arse until his nose touches the ground.
Very interesting, I like it.
It sort of reminds me of a Russian method of flaying I had read about in which a horizontal incision is made at the base of the neck and a small amount of skin is pulled back forming a bit of a pocket. Mercury is slowly poured into the pocket, and as gravity pulls it down, it separates the skin from the body all the way down.
So many possibilities...