In addition to being a lawsuit-grade Pitfall clone, Orpheus In The Underworld for the C64 is literally unplayable. Despite this, the title music is incredible.
The actual in-game music is just Can-Can, which I now know from researching this game is actually a piece from the titular operetta, Orpheus In The Underworld. The theme song is not, however. I don't know if it's original or what, but if you recognize it, let me know.
edit: it took me a couple days to realize that the particular vibe i was picking up was a similarity to part of the melody in one of the tracks of the obscure game Pitapat
