The world's best distance runners cover the route of the Boston Marathon in a little more than two hours. Not only is that pretty pokey, but they're exhausted when they're done. We have an easier way to see the course: We've videotaped all 26.2 miles, as the runners would see them if there weren't so many other runners, and compressed the trip down to about four and a half minutes of RealVideo. Join us for the ride, and fasten your seatbelt! (Video by Ed Medina/Globe Staff)