If you haven't seen the film, rent it. It is phenomenal. If you have, then you will know the references that website is speaking of.
The website is as haunting as the film.
First click on the red cirle/target. Then click on the word "proceed". Then click on "Otherwise proceed here". Do Pay close attention, you could miss something. Then click on the State of Virginia Seal. Read the report and type "y" for yes, to proceed. Do this again after reading the next page of the report. And again on page three.
From there click on the red "plus sign" that says "level 1 is active". It is all very game-like to get you into the subject matter of the film. (You have to type in the word "sparrow" where it says "she had the name of a bird") I would HIGHLY recommend that you see the movie. It will affect you.