You frequently use this thing when you're working on your video mashup collections, really brings it all together. That's the power of wacky effects and deep frying.
Each button has a specific function attached to it that messes the video up something fierce, although some fall more on the useless side of things. This one, for example, is just a long clip of someone screaming.
You proceed to press the button and listen to the anguished wail for many minutes.