I love it.
I'm recalling this from personal experience too, friggen' tailgaters SUCK. What really made this movie an instant favorite of mine is the excellent voice acting. I mean it really pulled the viewers into the storyline with all the frustration of being tailgated. The humor was creative and original, and that too was really going for this flash movie.
That paired with the good, smooth animation, is just a pleasure to view. The only thing that I think needed improvement would be the ending sequence. I felt that pressing the button scene was slow, although I like how you attached it to the guy's car, and the result wasn't as satisfying as I think it should be.
I mean these people have been tailgating you even after you put on the bumper sticker and electrical tape, the final solution should have the driver swerve a little bit, or slam on his brakes or something more dramatic in the final scene.
Still, all in all it was a great flash video and you better have gotten a good grade for that assignment, bro.