A blonde marine sergeant with the unlikely name of Serenity Carlyle taught me to shop, back on the World. Prior to that I had always employed a technique best described as precision purchase. You identify your target, you go in, get it and come out. You can't get what you want, cut your losses and get out equally fast. Over the period that we spent together, Serenity weaned me off this approach, and sold me her philosophy of consumer grazing.