First Persistent Environment Linux LiveCD

Any interesting twist to LiveCDs that many saw coming, Puppy Linux was the first to release a Linux LiveCD that burns your files and settings back to the very CD Linux loaded from. It's a special multi-session bootdisk that is about 50MB, leaving over 600MB for your personal files. Each time something is updated, it will burn the changes to your CD when you shut down. I bet Knoppix will end up with something like this before long. This replaces using a USB thumb drive to store you files because this works with a simple/cheap/disposable CDR (which the drive fills up from too many sessions, it simply asks you for a blank CD which it uses to burn a copy of itself and your (newly compressed) files ready for the next bootup. It's a slick idea!