It's a strange old world we live in but because everyone's rushing around stressed off their nuts we've developed a kind of 'me against the world' mentality and for a lot of motorists I imagine they see cyclists, and to some extent bikers, as some kind of evil delay on their journey.
Pretty much this.
I'm a business driver and cover 35,000 miles a year, I am also a cyclists and horse rider, so I see all this from three different perspectives and the 'me against the world' and 'I'm in a hurry and YOU are slowing me down' attitudes are seen everywhere, it is just that we are more vulnerable on our bikes.
I have to say I shrug most of the poor driving off, I know people are not really trying to kill / injure me, they are just being inconsiderate and selfish towards the outside world, and I confess to committing the occasional faux pas myself, although never on purpose.
All of that said, I do have a camera on the front of my training bike and I have reported drivers to the Police, although the results are usually random at best.