I am a woman of many obsessions, most of them short lived, last year, for example, was the year of the organic gardening, 6 or 7 big bags of soil, numerous large pots and a small bowl of chilis later and my enthusiasm had waned. This year has been the year of the moneysaving expert site, I cannot say how many free films I've watched, how many meals I've cooked from scratch or even when this current obsession will end, although I fear it has peaked.

But one passion of mine has stood...