This article made me consider the levels of physical pain I have experienced.

Ever since I had a monster kidney stone experience, I realized that most levels of physical pain are not so bad.

I have been stung by jellyfish, and it did sting, but it was nothing compared to a monster kidney stone, and I survived that (not saying that I would volunteer for the kidney stone again, though). The level of pain from kidney stone is deep, compared to sting of jellyfish, which is basically on the surface of your skin.

And BTW, after the stone operation, in the post-surgery room, a female nurse told me that she had experienced both child-birth and kidney stone, and she assured me the kidney stone is much more painful than childbirth.

So . . . altogether, as far as painfulness goes, jellyfish sting isn't nothing if you've lived through kidney stone. To volunteer for that level of pain though, I'd want a little more than three bottles of sun-screen. A few hundred bucks at least, plus the added benefit of knowing I did it to the benefit of my fellow man (cause I'm sure the sunscreen makers will be benefiting to the tune of some major bucks).