11:34 A.M. SATURDAY, JUNE 20, 2009, SAN FRANCISCO TextThismessage from London, eight hours ahead, meant to impress: is my dinner. Happy times! The accompanying photo: a pepperoni and sausage pizza so large it doesn't fit on the screen. Chris A., a fellow experimenter, and I were having our weekly virtual date. Text response from me: This is my breakfast. BREAKFAST. Can you hear the insulin pouring out of my eyes? Woohoo! Ante up, fat boy. My accompanying photo: two bear claws, two chocolate croissants, grapefruit juice, and a large coffee. Response from Chris: LOL ... please don't make me do this ... And so it continued, a text-message eating contest. The truth is, I do some version of this every Saturday, and thousands of people over the last four years have joined me in doing the same. In between pizzas and bear claws, the net result is that the average follower has lost 19 pounds of