Gimmick
In marketing terminology, the term gimmick refers to a unique or quirky special feature that makes something "stand out" from its contemporaries. However, the special feature is generally thought to be of little relevance or use. Thus, a gimmick is a special feature for the sake of having a special feature. It began, however, as a slang term for something that a con artist or magician had his assistant manipulate to make appearances different from reality. Such things as the manipulating of a gaming wheel led to the idea of a "gimmick" being used. Musicians often use gimmicks such as Slash's top hat, Angus Young's schoolboy uniform and Deadmau5's mouse helmet.