The Owner-Free Filing system
offsystem.sourceforge.net
offsystem.sourceforge.net
OFF does this, by not actually storing the copyrighted works themselves, but by storing two separate files from which the copyrighted work can be re-created, e.g. by addition or XOR.
This is not a new idea. However it is unlikely to work. The best refutation is the essay What Colour are your bits? -- http://ansuz.sooke.bc.ca/lawpoli/colour/2004061001.php