You completely forgot eDonkey 2000 (ed2k) and eMule. eMule got perfectly working DHT implementation including serverless file search. Technically it was much mo

You completely forgot eDonkey 2000 (ed2k) and eMule. eMule got perfectly working DHT implementation including serverless file search. Technically it was much more advanced than bittorrent, it didn't require .torrent files. It did fetch AHCI data from other peers. Only thing it lacked was efficient coordination between download and upload. Overnet (from ED2K developers) tried to fix that with Horde mode, but it failed because everyone was already using eMule. Hordre tried to pick 5 fast peers for mutual trading. Requirement for trackers and .torrent files felt really backwards stuff after using ed2k. The Gnutella with super hubs was called G2 protocol. Gnutella also utilized GWebCaches for retrieving bootstrap information of other active nodes.