The Mac serial ports were much better than PC serial parts. They ran faster and could be used over longer distances and had hardware support for networking with

The Mac serial ports were much better than PC serial parts. They ran faster and could be used over longer distances and had hardware support for networking with those cheap LocalTalk boxes - as I understand it, you're basically physically daisy chaining the computers, and the hardware is capable of looking at a packet and decide whether it's for this computer and if isn't it can pass it on without software intervention.