RaceMyRace, a website that interfaces with Google Earth to provide virtual tours of race courses of major US events provides access to the American Birkebeiner. Racers from the last two years can enter thei bib number to watch the race at their exact pace. Others can use the standard “pace setter.”
RaceMyRace also includes a number of major US running marathons.
It isn’t quite the real thing, but certainly fun to play with. It is easy to imagine such simulations becoming a useful visualization tool as technology allows for more realistic graphics.