I used to try to catch them and confront them or yell or something. In fact, in Lance's latest book, he talks about catching a truck after he and a friend were ran off the road. Three big guys got out! Anyway, now instead of losing my cool I either:

1. Blow them a kiss and smile
2. Hold up four fingers to signal that they should give me four feet when the pass next time.

Of course, they don't understand why I do the four fingers thing. It is more to help me keep my cool than anything else.