On the Special Features menu of Disc 1, select "THX Optimizer", there arrow to the LEFT to highlight a "Jack the Ripper" silhouette. Pressing ENTER takes you to a THX promotional video.
On Disc 2, selecting the scalpel will take you to the video "Jack the Ripper: The Final Solution".
On Disc 1, from the Main Menu, select the Language Selection Menu. Highlight "Main Menu" at the bottom of the menu and arrow to the RIGHT. You should have just highlighted an 'Eye'. Select it to view some hidden credits!
On Disc 2, from the first "Special Features" page, highlight the "Jack the Ripper: 6 Degrees Of Seperation" option and press RIGHT. You should have just highlighted something that looks like a fish hook. Select it to reveal a 40 minute documentary on the author of the book who inspired the Hughes brothers to make the movie!
All easter eggs were generously submitted by Satelk