I see people flip out when:
- Plane is running late
- Their train hits a snag: trouble on the rails, power issue, etc.
- Their bus hits traffic
- Their ferry is running late
Plane rage is the worst... but people (in the US) keep their cool inside the plane because they don't want to get sky-marshalled or put on a no-fly list. Then again I've never been in a "wait on the runway for 5 hours in the hot summer" situation.
The train rage is the next strongest of the three... though nowhere near as bad as on the road. And even if it was THAT bad, we don't have to worry about their anger making them screw up and accidentally kill a bunch of people with their metal battering ram.
The other two are minimal.
I speed, but not highly so. ~5mph on the roads, and usually only ~10mph in the right or middle lane. I DO get annoyed when the person in front of me is going UNDER the speed limit... especially after I watch them pass a couple of limit signs that they either ignored or didn't notice.
Beyond the obvious (spilling gravel out a truck, cutting me off) the only other thing that bothers me is people that don't pay attention at green-arrow signals. They tend to only stay green for 5-10 seconds and a person sometimes doesn't it appeared notice until it turns amber already.