I don't know how this thread got by me!
Tell your dd that there are lots of jerks out there, and to not take it personally. My trick is to tell myself that for every bleephole out there, there are a million good people. I also tell myself the jerk is having a bad moment in what may sadly be a bad life, and I'm lucky not to be him!
Also tell her she did the right thing by blogging about it, and that she shouldn't ever yell back at a car, because it's better to tell her story later to people who care. An aggressive person in a car is no match for a girl on a bike.
I hope this didn't spoil her ride. This is the hardest part of a great sport.