Afghans in need of a caffeine fix line up at Najibullah Sharyari's coffee cart in Kabul -- converts to the drink that is now percolating in a country obsessed with tea for centuries. Standing on a noisy street among vendors hawking their wares, the 30-year-old barista serves takeaway instant coffee from a mobile machine at his New York-style cart for as little as 28 cents a cup.