1. Paranoid. The white line is optional, especially when cars wish to pass legally in the other lane - must drive straddling both lanes whenevver threatened by the notion of sharing the road with others.
2. s. l. o. w. Those who have had maybe just a few too many tickets lately and insist on driving about 15 miles UNDER the speed limit...this drop in speed increases exponentially when talking on a cellphone (see also Paranoid).
3. F-F-F-A-A-A-S-S-S-T-T-T-!-!-! Those who, even when you're going maybe a mile or two over the speed limit, whiz by you and the other drivers like you're sitting at a light and they have the right-of-way-all-the-time-in-their-lane on a 45MPH road.
4. Roadblock. Limited to (sorry, roadskoller) local truck drivers who KNOW that the cars around them are no match for their heavy and large machinery so any rules of the road (like signaling to turn and actually stopping to wait for the opposing traffic to pass) do not exist in their world.
5. Overload. The car/van with a few too many people inside - and never a mechanically-sound vehicle either...usually belching clouds of oil-burning chokey, sometimes bucking violently from a transmission issue and always weighted so heavily with passengers, it's a wonder the suspension system doesn't come protruding out of the fenders above.