I think that music can be considered effectively infinite. Given constant changes in technology and timbral differences alone, any change in an existing piece theoretically renders it a new creation. (I didn't say that it wouldn't violate copyright law.)

I use Propellerhead Reason, partly as a sequencer, but partly because it is a massive software instrument. Just a casual sampling of what people have shared on their Music forum is enough to get a substantial inferiority complex. The variations and ingenuity in achieving same are impressive.

Take all the existing parameters of pitch, tempo, duration, timbre, key, orchestration, and maybe vocals, and anything I haven't mentioned or thought of. I think that original music is going to be happening for a long time yet. I'm thinking in geological terms here.

"My primary musical instrument is the personal computer."