When driving, what gets the most in your nerves?

I have found that not getting in any hurry is key to mellow driving. I've been down the Angury Driving road, and it is just stressful and no fun, so I now adopt a "hey, whatever man" attitude every time I get behind the wheel. You wanna go slow? Okay, I'll enjoy the scenery. You wanna go fast? Well, I'll slow down a bit when a passing zone opens up, fella.

Really, though, I dislike driving, and avoid it as much as possible. Given a choice, I'd rather bum a ride every time. You extremist drivers, defensive and aggressive, make the road a terrifying place.

Double Post:
This will probably draw a lot of fire, but a world where only professionally trained and licensed drivers could drive would be a heck of a lot more safe and efficient. Giving any idiot the right to pilot a two-ton bullet at 60+mph just doesn't seem like the most well thought-out plan. Take away personal vehicles and you've got less air pollution, and hey, with all the additional walking, there goes the obesity problem!

Jam it back in, in the dark.