On disc 2, from the Main Menu access the Interviews Menu located on the back of the train. Highlight the 'Bruce Willis Interview' and press LEFT. You should have just highlighted an 'exit sign' at the entrance of the tunnel. Select it to view a whole slew of great outakes from the film!
On disc 2, from the Main Menu highlight 'Trailer & TV Spots' and press RIGHT. You should have just highlighted the 'subway-train's standing-passenger pole'. Select it to view the disc's production credits!
All easter eggs were generously submitted by Satelk