A【MAD】Movie is a Japanese fan-made video, much like an anime music video (AMV). They are similar to Youtube Poop Music Videos but include more word splicing, other than pitch shifting. MAD can also describe the Japanese AMV community, although they can be anything from audio clips, edited pictures, to wholly original creations. MADs do not necessarily even need to be related to anime, though the more popular ones typically are.
MAD Movies can be divided into a number of subcategories such as:
Keyboard Crusher MAD Movie
【MAD】【KBC】 Justice Of Keyboard 【Seiken no Crusher OP】