Originally Posted by CommuterRun
I take all that stuff as an indication that I need to be further to the left in the traffic lane.
+2
I don't believe in being hostile towards motorists, but you need to be assertive. Be considerate, but try to set the right expectations (part of which is that you belong there and they need to adjust accordingly).
My experience is that motorists model their behavior off each other. When they see others being nice, just about everyone will be nice. When they see others being inconsiderate or abusive, others are far more likely to copy.
If you find yourself in a situation where lots of people are being aggressive, you need to either try to take control of the situation by becoming very forceful and assertive, or you can stop for a minute, let the jerks pass, and start fresh with a new batch of drivers that haven't seen (and won't be influenced by) others treating cyclists improperly.