Floating Mask

One way to indicate a Mask of Power is having it float. Sometimes, it means that the mask itself is sentient.

Note: That doesn't include masks which float with other items due to Selective Gravity.

Anime and Manga

 * The Noh mask in an Inuyasha episode "The Flesh Eating Noh Mask".

Comic Books

 * The Helmet Of Nabu, which gives Doctor Fate his powers.

Film

 * The voodoo masks in The Princess and the Frog, which represent The Friends On The Other Side.
 * Also, the Hell Gate the Friends on the Other Side use to at the end of the film, which resembles a larger voodoo mask.
 * The masks representing the ancestral kings of Atlantis in Atlantis the Lost Empire float and spin around the crystal that gives Atlantis its life.
 * Also, at the end of the film, a new mask, representing  is actually constructed by his daughter and son-in-law upon becoming the new rulers of Atlantis, which then floats away into the sky to join the other masks representing the dead kings of Atlantis.
 * And for some reason, the queens never get floating masks.

Literature

 * The haunted mask from the Goosebumps series.

Toys

 * Bionicle: the Ignika and Spectral Mask

Video Games

 * Super Mario Bros 2: Phanto, which pursue your character if you are holding a key.
 * Aku-Aku and Uka-Uka in Crash Bandicoot. Though a variation exists that they make the player invincible when worn.
 * The Legend of Zelda Majoras Mask: Near the end of the game, the titular mask.
 * Jalhalla from The Legend of Zelda the Wind Waker seems to be this and uses a swarm of Poes to create a body.
 * Sly Cooper 3: the Mask of Dark Earth
 * Banished Pantheon spirits in City of Heroes manifest as floating masks.
 * Vector Strong Bad from Strong Bad Zone. "Your Head Asplode!"
 * Yamask from Pokémon Black and White, which is a ghost connected to a mask, the former of which can turn invisible.

Western Animation

 * Tarakudo, the Big Bad of Season 4 of Jackie Chan Adventures.
 * An episode of Aladdin was actually about Princess Jasmine buying an evil floating mask at a bazaar.
 * One episode of The Simpsons was about Homer and Ned building a Bible-themed amusement park, with their main attraction being a floating mask representing Ned's late wife Maude. Unfortunately, it turns out that the mask is kept afloat by a leaking gas pipe, and their amusement park is shut down for that reason.