It is interesting, when the personal connection with the other party is not present or is reduced, how personalities can change. Email / news groups / etc. regularly erupt in flamewars, people making snide comments, etc.
The same thing happens often when people get in their vehicle. In their own little world, drivers aren't always as aware of their actions and behaviors as they should be (or how their actions impact other drivers, for instance).
I know I have been guilty of this from time to time.
This is another call to really just bring an awareness to your actions and who/what they may affect.