People get mad when they get scared, and being buzzed is scary. It's good to remember that this is happening -- just to remember that your buttons are being pushed. Also good to remember is that a driver, when confronted with an angry screaming person, is going to have their buttons pushed in the exact same way -- it's a threat situation, and the same scared -> mad thing happens. That's how the two of you end up going at it. Easy to say, not so easy to not act it out...the proverbial "count to ten" is probably about as good as it gets for breaking the scared->mad reaction cycle.