That brought back memories of playing off a backup and having to switch to the original for validation, and of some Amiga program that claimed to copy copy-prot

That brought back memories of playing off a backup and having to switch to the original for validation, and of some Amiga program that claimed to copy copy-protected disks. It thrashed the floppy drive like crazy and looked very, uh, sophisticated (as in lots of virtual indicator lights blinking away on-screen), but I was never convinced that it actually worked.