MTV-Overdrive hosts a set of four featurettes on David Fincher's "Zodiac", mainly interviewing the actors, talking about the roles and their experience of meeting their real-life counterparts.
Each of these is 3 minutes long, so by the rules of fundamental algebra this is a total of 12 minutes of ZODIAC info. -- Amazing!
This first click should get you to a continous play:
If that doesn't happen for whatever reason, here are the individual links:
Obsessing over "Zodiac"
Getting to know you
What would the case be like now?
David Fincher's "Opus"