PA has a law like this THAT WAS JUST PASSED LAST YEAR (not 5 years ago). You cannot travel in the left lane for more than 2 miles or they can ticket you. Usually I'll give 'em about a mile before I get nasty with the highs or a horn. Sometimes if you just move a little left and throw on your left turn signal, they'll get the idea. If not, downshift, pull right then left (or on my bike, lean right/pull left, flick, lean left/pull right wave goodbye).