This is such an emotive subject!
Having commuted to work for the past few years, I can identify with all that's been said - and especially with Lynne.
It's so hard to keep your cool when you know that some car drivers are intentionally trying to run you off the road, or ride straight through you.
I started off being polite to drivers, but after months and eventually years of being abused on the roads, I developed a deep seated road rage with everyone who crossed me.
One day I got into an altercation with a guy who took exception to me not yielding to him, even though he was behind me at a junction. This developed into a heated argument, him trying to run me over, me banging on his window, him taking chase after me, deliberately trying to run into me. I again caught up with him and banged on his window and he then got out of the car and came at me to punch me. I think that it was only because I was a woman that he stopped.
To cut a long story short, it's so difficult not to express your anger when someone does something crazy - but I was stupid and learned my lesson.
Now I grit my teeth and for the most part take my anger out on my pedals.
I always try to make eye contact with people who are turning in front of me, and will put my hand up in the stop position if I think they're gonna cut me up. On the flip side, I also say thank you to patient drivers who I know could have pulled out in front of me, but who waited.
Despite the fact that cyclists are so abused on the roads, it's stupid to get into arguments with drivers because you never know where it will end.
I know that sometimes I'm guilty of taking the moral highground - I'm one less car, yes, but I should also have consideration for others and shouldn't get annoyed if someone slows me down, makes me stop whilst in full pelt, or blocks the road so I can't sail past.
Of course, endangering my life or my bike is another thing, but I think the cooler, patient (but assertive) approach is the better.