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Bonus Feature:
Disc 4: Press your Up button from the Main Menu. A question mark will appear on the orange booth. Press your Enter button for video of the Simpsons ride at Universal, Orlando.

Deleted Scenes:
Here's a list of episodes that have easter egg deleted scenes, to access them you have to click the items listed in the top panel:
Beyond Blunderdome (2) Crystal Ball and Notepad
Hello Gudder, Hello Fadder (1) Crystal Ball
Eight Misbehavin' (1) Crystal Ball
Take My Wife Sleaze (1) Crystal Ball
Little Big Mom (2) Crystal Ball and Notepad
Faith Off (1) Crystal Ball
The Mansion Family (2) Crystal Ball and Notepad
Sadlesore Galactica (1) Crystal Ball
Alone Again Natura-Diddily (2) Crystal Ball and Notepad
Bart to the Future (1) Crystal Ball
Days of Wine and D'ohses (1) Crystal Ball
Kill the Alligator and Run (1) Crystal Ball, though it's actually A Promo Card.
Last Tap Dance in Springfield (1) Crystal Ball
Behind the Laughter (2) Crystal Ball and Notepad