In case you don't know this one already, I might have found yet another movie-site for you to bookmark: chasingthefrog.com/reelfaces.
What this site does, and with great effort, is to compare films to their real-life source materials, which may be stunning for "Zodiac" -- but at least equally awesome for films like "The Exorcism Of Emily Rose", "Walk The Line" or "300".
In the case of David Fincher's recent directorial achievement this site has comparisons of the actors faces with their real-life counterparts, an exhaustive Questions & Answers section, answering such inquiries as "Did the two Zodiac survivors want the movie to be made?", "Did a police officer really spot the Zodiac killer after the Taxi cab murder?" or "Did Robert Graysmith really visit the home of a man who had been friends with Zodiac suspect Rick Marshall?"
The site also features an interview with Zodiac-Survivor Bryan Hartnell and some further links for the movie and the case.
This is great fan-stuff! Must check this out: