Re: "two monitors plugged into each other, a USB mouse plugged in to an ethernet port"
I would guess the monitors had DVI or VGA connectors and someone used a cable to connect between the two.
When personal computers were first coming out I was working in the computer centre of a very prestigious college in London - . I'd installed a CP/M machine for someone who's job title was programmer. So she was a programmer in a professional computer centre in one of the top centres of excellence for technology and science in the UK. A couple of weeks later I got a call saying I must come down "at once" to mend the computer. I was finishing off what I was doing and was about to leave for her office when another call came in; "You don't need to come. Someone spotted it wasn't plugged in."