Some time ago I wrote a tutorial about the copy protection used in the Amiga version of Street Fighter 2. The tutorial explains the inner workings of the custom disk format used and how to rip the data from the copy protected disks and reconstruct working (and copyable) AmigaDOS disk images.
The tutorial was originally published on Flashtro.com (great site btw!)
Download the PDF:
Street Fighter 2 – Amiga MFM Protection
Security Impact 