I am not the marathon driver. I break them up with stops at national parks and stuff life that. I don't have the physical issues you guys mentioned (knock on Bussekin steel), but I find audiobooks to be the cure for the mental part of it.
Never thought about audiobooks, but that could work well. I had a satellite radio in my car, and that worked great for distance driving, but I rarely go over an hour away from home now.
