A little (a very little) global warming humour: Q. How is the recently concluded Copenhagen climate conference like the Medieval Warm Period? A. They both may be seen to disappear when it serves a noble purpose. Well, I warned it was very little. But, then again, global warming is a very earnest, if not positively sullen topic, and to mine even an atom of a joke from all of the frenzied evangelism of self-appointed environmentalist groups, the grim coven that ran the now celebrated labs in East Anglia, or from our modern day catastrophist Savonarola, Al Gore, is too much...