I've had both cars and truckers do it to me a zillion times over and just slow down and drive like that for over five miles and they blow their horns continually so I slow down even more. They keep blowing there horn so I slow down even more then they move to another lane give me the middle. I give them a big smile and a wave. I'm sure I've pissed them off big time since they didn't get the reaction from me that they wanted by giving me the middle finger. lol