After you finish the game, watch the credits (not like you have a choice -- you can't skip past them) and watch for a screen that tells you the password for the "Special" menu. It's only there for a short time, and after the credits are done the game closes automatically and dumps you to the desktop, so watch carefully. (It may be different from game to game, but in my game it was "brighteyes.")

Entering this word into the Special menu gives you access to a great many bloopers from the voice recording sessions.