Metroid Prime 3: Corruption
Metroid Prime 3: Corruption
In one of the trailers for Metroid Prime 3: Corruption, there's an introduction to the Aurora Units that feature heavily in the game. The camera pans over blueprints for what the game calls a future Aurora Unit complex. The layout is identical to Mother Brain's chambers in Tourian from Super Metroid.
Contributed by CosmykTheDolfyn
In 2005, rumors spread of a new side-scrolling Metroid game known as 'Metroid Dread", which never materialized. However, in Metroid Prime 3: Corruption, scanning a computer screen in game reveals the message "Experiment status report update: Metroid project 'Dread' is nearing the final stages of completion.", most likely a nod to Metroid Dread.
Contributed by CosmykTheDolfyn
The player can get bumper stickers on their ship by having certain save game files in their Wii's Memory. This includes games released after Metroid Prime 3. The games are:

Excite Truck.
Wii Sports.
The Legend of Zelda: Twilight Princess.
Wario Ware: Smooth Moves.
Wii Play.
Super Paper Mario.
Mario Party 8.
Metroid Prime 3: Corruption.
Super Mario Galaxy.
Super Smash Bros. Brawl.
Contributed by Cavery210
The Japanese version of the game includes a questionnaire. Once it's completed, the game recommends a difficulty level for you.
Contributed by IkiFoo
Corruption was the first Metroid game to feature extensive voice acting. While most of the game's voice actors aren't well known, anime fans may recognize Rundas' voice actor as Christopher Sabat, better known as the voice of Vegeta and Piccolo in Dragon Ball Z and GT.
Contributed by MightyKombat
In the original version of Metroid Prime 3, Admiral Dane shouts, "Damn! They're targeting the planetary-defense system." The word "Damn" was replaced with "No" in the Metroid Prime Trilogy though, likely to remove a possible swear word from the game.
Contributed by gamemaster1991
Entering certain numbers on Samus' communications console in her ship will trigger special messages from 5 of the Metroid Prime 3 lead developers: Satoru Iwata, Kensuke Tanabe, Shigeru Miyamoto, Kenji Yamamoto, and Yoshio Sakamoto.
Contributed by Pogue-Mahone