I try not to care about hostile drivers and just ignore them.
Really, you should just feel sympathy for them. They are most likely hostile because they are stressed out about getting to and from work, to pay for their expensive car and other things they don't need. So, yeah, I just try to zen out, and in general give them my sympathies for wasting time in a car.
Meanwhile, you are being a badass riding, your bike powered by you.
I used to be all agro about riding, but then I realized it did no good, and actually made be feel worse off in the end.