We used to play RA on my friend's home network, which was thin net running IPX. The house rule was that if we'd collectively built enough units that the game started slowing down you had to attack. It was good times.

When it worked, IPX LAN was maybe the peak UX in multiplayer gaming.

Moving everything to TCP/IP came with a lot of improvements, but we also lost important things. Reminds me of the move from Flash to HTML5.