for Grim Fandango get residual - http://residual.sourceforge.net/

...taped behind your balls?... that's the first place they look... just replace one of your digits with a prosthetic and you could have a literal 'thumb' drive

"With optical media the reading mechanism is separate from the media the data is stored on which means if part of the reading mechanism fails the disc can easily be removed"

isn't that part of the problem with optical media? Every trip from storage to the reader is an opportunity for damage to occur. At least a hard drive's disk is kept safely in a metal box away from humans.