That said, these guys are impressive. You may remember Charlie Engle, who went on to participate with Marshall Ulrich in his run across America. (See my review of Running America.) Ray Zahab continues his ultrarunning, having run across the Atacama Desert in Chile and preparing for a run across the Gobi Desert in March of next year. (Follow his exploits at http://rayzahab.com/rz.)
Next time you're feeling awesome that you finished that 10K or marathon, check out these guys. They'll challenge you to do more than you ever thought you could do.