I've seen apps and software being able to use files directly from a Dropbox or Sugarsync (orr Box.com) account, rather than uploading these files to the app server. I'm thinking this could be used for the Jukebox, as an alternate source. The files would still say private within a campaign (since the GM would need to enter his Dropbox credentials) and would therefore be responsible for the copyright issues. The files would stay in the dropbox account, and they would never hit the roll20 server.