+1 on the phone. Snap a picture of her license plate and of her face. A major factor in road rage is the feeling of anonymity and freedom from consequences. Burst that bubble, and they may start actually thinking about their actions.
(Or not. There's always going to be some risk in doing anything the driver may perceive as escalation, and the safest route is probably to just get out of their way. It's up to you whether the choice is worth it.)