Disklavier

I bought one of these:

http://www.amazon.com/gp/product/B000M3GODW/ref=oh_details_o00_s00_i00?ie=UTF8&psc=1

Though I've not used it yet.

My understanding is that the only thing "non-standard" on the disks is that they didn't write a sector 0.   You can't directly mount it with the standard PC software, but if you can access the raw disk, you will find a dos FAT filesystem there.     There is DOS (real DOS unfortunately, not stuff that can run on Windows) to access this.  I  figure when I get a few days I'll write MAC software to use the thing.