From its beginnings in France, and the lurid "pulp" and true-crime magazines of the 30s and 40s, the girlie-mag genre was perfected in the USA in the 1950s, and Hugh Hefner's pioneering Playboy is only the most famous of its type. Some of these vintage erotic magazines sold in the millions, to Americans at home and US servicemen stationed abroad. Flourishing in the more relaxed censorship laws after the war, the number of publishers of this kind of material seems at first overwhelming, but look a little closer and you'll find that many are published using the same addresses or, when the going gets really tough, from P.O. Boxes, always one step ahead of the law - sending porn through the post was a Federal crime.