The Week catches up on a few years' worth of "minor to major" edits to well-known sad or dark songs, upsetting the mood to happy or humorous effect. Embedded here is The Godfather theme, which when modified sounds rather like the theme tune to the arcadian British show Last of the Summer Wine, about old Yorkshiremen enjoying their endless retirements. https://www.youtube.com/watch?v=kyVq85xrTCY
Someone should make that sound tragic and sinister instead, a sort of "Last of the Middlesborough Vodka."
Also:
https://www.youtube.com/watch?v=3ppoRHBtwCY&feature=youtu.be&t=2m27s