Trivia: Happy Feet
- All-Star Cast: Nicole Kidman, Hugh Jackman, Hugo Weaving, Brittany Murphy, Elijah Wood, Robin Williams and Steve Irwin.
- Dueling Movies: With Surf's Up. Happy Feet was the clear winner financially, but both went over well with critics.
- Hey, It's That Voice!: Tommy Pickles of Rugrats is young Mumble, and Frodo Baggins of Lord of the Rings is adult Mumble. And The voice Hank Azaria's used for Anastasia's Bartok is reused for Sven; other than the lilting Swedish affect, it's almost identical.
- Fans of The Catillac Cats will recognize Danny Mann as one of the Skua birds (the one that keeps getting called an idiot).
- The Other Darrin: Pink is the new voice of Gloria in the sequel due to Actor Existence Failure on Brittany Murphy's part. Common replaces Fat Joe as Seymour in the sequel.
- Talking to Himself: Robin Williams, in a rare example of it being pretty obvious.
- What Could Have Been: As mentioned on the main page, the film was originally going to have actual aliens.
- Also, some Happy Feet storybooks and posters show Mumble as a fully-fledged Emperor Penguin. This is because until late in the film's production, it was intended for Mumble to lose his down feathers during his pursuit of the fishing fleet. However, it was decided that Mumble would keep half of his juvenile down throughout the story, to make him different to the other Emperor Penguins. Here are a few images of adult Mumble:
- Mumble moulting: