(Spoiler) about the last scene in the movie

SPOILER ALERT if you have not seen the movie, go away!

I was not an avid Two and a Half Men fan, but I assumed that the scene at the end was legit. I thought they had reverse-engineered that scene into a movie, and then sprinkled in some bits from Planes, Trains and automobiles, Smokey and the Bandit, and Cheech and Chong.

I just saw in the IMDB trivia, that the scene was filmed exclusively for the movie. I think I liked it better thinking it was a real scene. I guess it would've been too much of a spoiler for anyone who had seen it in advance.