Be careful before yelling at drivers. They are in big, heavy, powerful vehicles. You're on some 18 lb. contraption that offers no protection. I've tried all kinds of strategies in dealing with discourteous/dangerous drivers. the best for me has been to spread my arms and open my hands palm upward as if asking "what the hell are you doing?" They can usually see me in their rear view mirrors. Very non-confrontative. Sometimes I've been able to catch up with drivers at lights and tap on their windows. When they lower them I point out what they did. This is a friendly way to do things but not always effective. I've gotten into arguments this way.