Cursor Fairy

The Cursor Fairy is a character from The Legend of Zelda: Twilight Princess. Only appearing in the Wii version of the game, the Cursor Fairy does not play a role in the story and is purely used as a cursor. Although it follows Link around like a sidekick, the two never interact and it is not known if the fairy is truly there or not.

Theory
The Cursor Fairy bears striking resemblance to Navi from The Legend of Zelda: Ocarina of Time. Although it is never stated directly, many believe the Cursor Fairy is either a reference to Navi or Navi herself.