Memories are not held in their entirety in the brain like old movie clips, but are maintained as a kind of chemical residue of the original perception, which could be thought of as a hash value or remainder, but not a one-way algorithm at all.

FORBES: Density Of Meaning: Creation As The Flip Side Of Memory

When MP3 rolled around and Sony's walkman customers were clamoring for a solid-state MP3 player, Sony let its music business-unit run its show: instead of making a high-capacity MP3 walkman, Sony shipped its Music Clips, low-capacity devices that played brain-damaged DRM formats like Real and OpenAG.

ENGADGET: Microsoft Research DRM talk