This actually makes me think of a project I'm currently neck-deep in working on... Taking captured audio hardware register writes (in the form of a VGM file) and having a modern microcontroller actually replay them on an actual NES CPU.
In other words... A hardware-based NES game music player.
(Of course I'm not actually visualizing much, yet.)
NSF is a cool format, itself. It's basically a specialized ROM format for encoding game music and sound effects for playback, usually in an emulator. And since it relies on actual CPU code rather than recorded register writes, it can include loops and such programmatically.
This one I think is especially cool. Instructions to build a cartridge to run on an unmodified NES: https://web.archive.org/web/20170319202533/www.nullsleep.com...
And these two both use an NES (or Famiclone) CPU, along with some other hardware:
http://kevtris.org/Projects/hardnes/
http://forums.nesdev.com/viewtopic.php?t=5957&view=next
NSF is a cool format, itself. It's basically a specialized ROM format for encoding game music and sound effects for playback, usually in an emulator. And since it relies on actual CPU code rather than recorded register writes, it can include loops and such programmatically.