Yoko Ono's 1961 artwork Painting to Hammer a Nail is a white painted wood panel with a hammer hanging from a chain attached to it, and a box of small nails sitting next to it.

The title and the stray nails already in the board suggest that you should, in fact, use the hammer and hammer your own nail.

Last week when I was in the show I heard much hammering. And here's what the painting looked like at the end of the week, when last I saw it.

Well, it seems the storm of weekend visitors had other ideas. This is what Painting to Hammer a Nail looked like Monday morning.

Yoko, what do you think?

And here's a sweet (true or not, I don't know) story about this piece, John, and an imaginary five shillings.