I would have to go with dir. commentaries, deleted scenes and the making (the thought of having a diff. cast just makes you wonder what would have become of the film, hehehe). Knowing Puzo did it for money was a blast too (easter egg).
DC
"Life is so beatiful" - Don Vito in The Godfather novel "My name is Michael Corleone...There are people who'd pay a lot of money for that information" - The Godfather