This would be one of the many reasons I record all shows and watch them later so I can skip commercials. And if I do happen to watch live TV I usually get up and do something during commercials.
And on the radio when a commercial comes on that annoys me (like this annoying tooth fairy one for a local wireless phone company) I will switch to my CD for a minute.

I just put my holiday CD in my car. Trans-Siberian Orchestra. I rocked all the way to work.