Um....
5 Akubras: Cattleman, Riverina, Rough Rider *giggles*, Stylemaster, Traveller
5 Cowboy hats: The Nevada, the Gus, the Dakota, the Gambler, Pinchfront
5 Top hats: the beaver hat, the high hat, the cylinder hat, the chimney pot hat, the stove pipe hat
5 Famous movie hats: The Indiana Jones, the Freddy Krueger, the Marty McFly, the Captain Quint, the Depp Wonka
5 Meta-hats: the Monopoly hat, Sir Tophamhat, The Mad Hatter, a rabbit-filled Magic hat, Hats in the air
5 famous sharks