That happened to me a while back on the NY State Thruway. Minivan full of kids, the driver changed lanes as I was passing him on the left at around 80mph . . not considered speeding there, since everyone normally does around 75. Thank goodness there was a left side shoulder and I was able to avoid them. Needless to say he felt really stupid after that, and stayed well behind the pack of cars we were traveling in. As long as I know that he realized his stupidity, that was enough for me. But things could have been worse with those kids in his vehicle.