For other drivers that make you angry, roll down the window, stick your arm out, extend the middle finger and shake it, shake it, arm and finger both, repeatedly.
You come to a stop light, someone behind or beside you has a loud, thumping stereo system. Exit vehicle, kick vehicle repeatedly. Or pound on the windshield with your fists, alternatingly putting fingers to your ears. Or climb up on the hood and jump up and down. Great exercise!
If you have a passenger along that criticizes your driving skills, punch-punch-punch! Another great exercise!
At a long stoplight, wave to drivers behind you, beside you, over and over and over again. And if they don't wave back to you, or they suddenly get on their cellphones with a worried look on their faces, just keep on waving. Good exercise, once again!