Could extend this so that file continues to exists as long as any peer who has downloaded keeps their window open. So, I share a file to a friend, he downloads, i close window. His window still open therefore link still valid. Similar to this <a href="http://ephemeralp2p.durazo.us/2bbbf21959178ef2f935e90fc60e5b6e368d27514fe305ca7dcecc32c0134838" rel="nofollow">http://ephemeralp2p.durazo.us/2bbbf21959178ef2f935e90fc60e5b...</a>