I'm all about blowing a little smoke with the diesel, but this guy is just being an asshole... LiveLeak.com - Cummins Diesel vs Bicyclist!!
The fact that this event was taped pretty much answers the question about the intent of the truck driver. Complete A hole
Lulz would be acquired when he is reported for this, and then gets in trouble for having a polluting vehicle.
I think he is either being stupid, or tree huggers really pissed him off, so he is doing it on a purpose...