Superman Returns : Two Disc Special Ed. Easter Egg - Hidden Outtake Reel

On disc 2, go to Deleted Scenes. Then, hover your mouse below the "S" in "Features". When the Superman "S" appears, click on it. You'll be taken to an outtake reel featuring Lex Luthor and Lois Lane.

Another method is to simply press down (if you're using a remote control) until you get to "Features". Simply press down once more, and the same logo will appear.