If a thing is worth doing, it's worth doing under ludicrously difficult, not strictly necessary, self-imposed rules. Such was the thinking of 31-year-old Graham Hughes when, stewing on the details of a long-dreamed of plot to visit every country on Earth, he decided to add a bit of hot sauce: He would visit them all in one continuous journey, and — to hell with it — he'd also do it without flying. Why not?