I'm a big fan of dvd commentary. It's usually the first thing I do when I buy a dvd since I ususally buy dvds after I've already seen the movie. I usually prefer a cast commentary but depending on the movie and the people involved I'll watch director/producer commentary as well. I watch commentaries almost equally as much as I watch regular movies and tv.
I once had a LOTR marathon (12 hours or so) watching the cast commentary and I would totally do it again.
When I first got Repo The Genetic Opera on dvd I watched it, then I watched it again with my mom, then I watched it with the first commentary, then I watched it with the second commentary. That was all the same day, back to back, I just couldn't get enough of it and I wanted to know everything about it.
I also really like watching the commentary for my favourite tv shows. I will watch an entire series and then immediately watch it again with commentary if it's available. The most recent ones I did this with are The League of Gentlemen, Psychoville, and Red Dwarf.
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My dream is to one day know what my dream is.
~Michael Novotny