Protocols that have not changed in the last 30 years
For years I wondered about the insanity of the FTP protocol.  Why take random ports at both sides?  Did they hate firewalls?Some day, someone explained this allows for a client(with low bandwith) to setup a transfer between 2 servers(high bandwith) with the data not moving through the client.  I've never seen this usage and don't know any ftp package supporting this, but it's pretty neat nevertheless.