There's no way that Christianity's founders could have predicted what I consider to be the eighth deadly sin: rude driving. A few of the seven deadlies might already cover it-greed, wrath, envy or even pride-but I believe it belongs in its own category. Surely Dante would add a thirteenth circle of hell for aggressive drivers.

You know what I'm talking about. The Me-Firsters who swerve in and out of traffic-only to end up stopping at the same lights as you do. The tailgaters who inspired one of my favorite bumperstickers, "Unless You're a Hemorrhoid, Get off my Ass." My favorite is the guy here in Longmont, Colorado, who bought a traffic light changer for $100 on the Internet and screwed up the morning commute for months before the cops finally caught on. Then he had the gall to tell a reporter he did it because he was always running late! Uh, hello, there's a better solution to that problem! His sin is in a category all its own. Solitary confinement in hell, with frequent visits from Satan himself, would be about right.

I learned to drive in Los Angeles in the late seventies, about the time that a new trend came out of the Land O' Fruits and Nuts-freeway shootings. My driver's ed instructor repeatedly said that automobiles can be a deadly weapon. Who knew that bad manners behind the wheel could be just as lethal? Keeping your middle finger to yourself on the road became a matter not just of good breeding, but of survival. I think it's the reason why driving in L.A., while still potentially a contact sport, is overall a much more courteous experience than anywhere else I've lived in the United States. When you need to merge in bumper-to-bumper traffic on your way to Disney Land, you have a good-to-excellent chance of encountering drivers who will slow down and let you in. If you think I'm being too kind to Angelenos, I have just three words for you. Miami. Seattle. Boston. It's every man for himself in those places.

I'm hardly blameless, though. When I'm having a bad day, I'm more susceptible to the rude driving bug. I compare my progress to the guy in the SUV roaring up in the lane beside me, and I speed up. (Envy) I gloat as I pass the compulsive lane changers on the Diagonal Highway to Boulder. (Pride) My kids are well aware that "jack ass" is my favorite term for jerks in traffic. (Wrath)

But wasn't I talking about other rude drivers? Don't even get me started on people who think they can drive and talk on their cellphones. A fourteenth circle of hell, anyone?

Diana Shellenberger is an author whose essays have been published in national newspapers and magazines. She is writing a novel, Nothing Left but Joy, and is also compiling a book of short stories. She lives in Colorado.