DVD Video Cheats: Toy Story 2 (3-pack supplemental disc) Cheats

Hidden Joke Reel
Go into the "Story" menu within the "TS2" section of the supplemental features disc (Disc 3). On the next menu, select "Jessie's Song"

After the next menu pops up, arrow to the left - which will reveal a hidden question mark

Selecting the question mark will activate a clip with director John Lassiter. He congraulates you on finding the egg, and then he invites you to view a gag ending to the movie's song.