The first thing that came to our heads

"Monster Mash," "Crocodile Rock," and "Jailhouse Rock" are all real songs about other, fictional songs that share the same titles as the real songs. Any other examples? And is there a name for this kind of song?

Actually, "Monster Mash" is technically about a dance, not a song, but still, it relates a story which logically presumes the existence of a fictional piece of music pre-existing the real song, and (the peculiar thing is this my friends) leaves open the possibility that the referenced fictional song might not resemble like the real one.

Oh, hey, "Time Warp" from Rocky Horror is another one.