If your a motorcyclist try the Dragon which is Highway 129 from the Tapoka Bridge across the Tennessee River in NC to the foot of the mountain in Tennessee. It's eastern canyon racing for motorcycles.
Just be careful a lot of people have died there this year.
Very good point, it has become a danger even for four wheel traffic due to the racers. Check it out on youtube to see some cool but insane videos of the activity.
Well like it has been said the crotch rockets that run this section are crazy. Try and do the run sometime through the middle of the week as there is less traffic on the road then.
My wife and I rode our Harleys from Middle Tennessee over to the Dragon for our anniversary. Did the Dragon on the way in to Fontana Dam...stayed at the incredible hotel there...had a five star dining experience...and then came back home via the Cherahala (mile high) skyway. Both highly recommended for bikes, sport cars, and convertibles!