It all began with a poem called Warning, by Jenny Joseph, that goes like this: When I am an old woman I shall wear purple/With a red hat which doesn't go, and doesn't suit me. Hundreds of thousands of women of a certain age have taken up that poem as their anthem and that red hat as their badgethey (we) will do anything we pleasesociety's constraints beware There is the Red Hat Society and there are conventions and tshirts and now...