How about not going the route of "zen the #$%^ out." I prefer the drivers around me to be aware of their surroundings and conscious of their driving, not lost in dreamworld.
Driving in a congested freeway does not need all your faculties. Most people do it on auto pilot.
When you are fully alert, it leads to frustration , lane jumping and road rage. So I agree with GP that you need to mellow yourself down during long stop-n-go traffic. Not to the point of falling asleep on the wheel of course. But I don't think everyone needs to be combat ready either.
When I'm stuck in traffic, I consider that a time to submerge the ego, embrace the virtue of patience, and realize that the goal of all drivers should be for everyone to get everyone unstuck and return to normal traffic flow.
So rather than sit bumper-to-bumper, I will open a car-sized space ahead of me, and intentionally allow "line jumper" cars to enter it. Rather than alternately hitting the gas and brake, I'll just let my car roll, smoothing out the wavelike interactions in congested traffic.
If you stop thinking purely of your own self-interest, you can act to improve the overall flow of traffic, rather than just try to get yourself out of it as soon as possible. Think of it as an engineering problem. Instead of how to get 1 person home as quickly as possible, try to get 10000 cars to their destinations with the lowest median travel time, using only your ability to control one car in the flow of traffic.
