So, I'm walking around Powell's City of Books in Portland, Ore., a couple of days ago, and my eldest daughter, Clara, says there's something I have to see. All too familiar with my professional interest in machines, she leads me around a corner, and there is a refrigerator-sized machine attached to an industrial Xerox printer on one side and a sleek Epson print on top of the other side. Together, they're busily printing pages and paperback covers, and then turning out full-sized, physical, hold-in-your-hand books!