Mr. Blake derived a simple melody by playing a few dozen digits of pi using a C-major scale, with 3, 1, 4, 1, 5, 9 translated to the notes E, C, F, C, G, D and so on.
WSJ: We Can All Have a Slice of Pi | Postmodern Times by Eric Felten
2.
When I was a teenager I saw a website suggesting pi could be a song, with one as middle C, two as D, three as E, etc.