I really liked A Very Harold and Kumar 3D Christmas, and one of the best scenes in it is Neil Patrick Harris' musical number. There's something about the raunchiness of Harold and Kumar as well as the combined cheesiness of musicals, Christmas, and 3D that just makes it amazing. Watching the video storyboard for it is pretty fantastic. You can tell exactly what they want to do with the final result, and their attempts to make it look as ridiculous as possible are even better considering how few people are working on this.
If you're worried about spoiling the movie for yourself, don't be. While it is a bit funnier seeing the video after knowing the full sequence, it gives you a great idea of what's to come in the full movie.