Killing each other in the backseat, or how to prevent car fighting

Do your kids sometimes act as if they're trying to kill each other while you drive? Not only does it create a safety hazard for the driver, but it's darn annoying! And if you have enough kids (3 or more), then they're going to be arm's length from each other in their seats so incessant cries of "He's touching me!!" are almost impossible to avoid.

I have two weapons in the fight against car fighting. One is called The Car Time Out. In this, Mommy just pulls over as soon as she can (safely) do so, and grabs a book or magazine. It takes said children a moment to realize what's going on. Suddenly it dawns on them that 1) sitting still is less fun than beating your brother to death with a book and 2) MOM IS IN CHARGE. Gasp! We had better straighten up if we ever want that ice cream, storytime, or visit to the park.

The second weapon in audiobooks. These are a real blessing because even non reading children get caught up in the story, and so there is no pressing boredom- induced urge to throw Legos at a sibling. Lately we've been listening to Billy Brown and the Mystery Package by Kiddio.

So how do you deal with car fighting?