I also can't stand when people purposely try to slow you down. I've found that if you bide your time, there will be an opportunity to dash into the other lane and blow by the idiot blocking you.
As far as high beams, beware in New Jersey. I actually got pulled over 4 years ago and ticketed for flashing a driver who pulled into the passing lane going 20-30 MPH slower than I was going. That driver almost caused an accident...at least it was my old car and not the F10!