This blogger posted the following video and I had to steal it.
My niece and brother-in-law just ran a marathon over the weekend, and I'm betting most of this went through their head at some point.
I, myself, have never run more than half a mile and don't plan to unless I'm chased by a bear. And even then, I might try out that fetal position trick instead (that's how much I hate running).
In any case, I'll never know what running 26.2 miles is like, but this video gives me a little insight: