A character thinks and thinks... then, suddenly, has a bright idea! A light bulb turns itself on directly above the character's head. Often with character pointing one index fingers upwards. This trope has been subverted for decades -- it became a cliche almost as soon as it was invented (in the 1920s, for the black and white Felix the Cat cartoons). Also, this trope may have been invented in reference to a Mr. Thomas Edison having a great idea about something... what was it again? (Or it could just be the concept of enlightenment. Or having a bright idea.) Examples of Idea Bulb include: