My favorite part of a lot of movies is the blooper reel. Sometimes I skip right to it in the special features on the Blu-ray because nothing makes me smile more than watching celebrities f*ck up their lines. Occasionally we are treated to having these bloopers run during the end credits of a film, but thanks to YouTube and websites like Funny or Die, we can get them online.
This reel for THIS IS 40 is full of funny moments. You can see the actors working on their improv which director Judd Apatow is known for including in the final cut of his movies. It is also funny to see how an actress like Megan Fox, who is not used to improvisation, cracks quickly under her costars unexpected lines.