When a Beatles and Super Mario song have the same chord progression 

First half both use the 1,6,4,5 progression approximately, which is not interesting in itself since it is a very common progression, but it makes for a fun mashup when putting the vocals of one on top of the other.
Instrumental: The Credits Roll- Super Mario 3D World
Vocals: Octopus Garden - The Beatles
Soundcloud link: / when-a-beatles-and-sup...