25 Great Unscripted Movie Moments [VIDEO]

Though the title of the video is "Greatest", I have to debate the supposed greatness of some of these adlibs, such as "Dumb and Dumber" and "40 Year Old Virgin".  Nevertheless, it is still terrific to see that some of the most iconic and memorable movie lines/moments weren't intended to be in the movie in the first place.  Enjoy!