@JayEye - if you don't use the mobile URL for xkcd the chat room expands it out for you. Like this:
@Paul See <http://www.gammon.com.au/forum/?id=11428> - there seems to be a school of thought that RS485 (obviously not Ethernet per se) needs a ground as well as the balanced lines. I'm not sure about Ethernet. It's a good question.
@JayEye You could possibly re-word. What is the post in question?
Our Arduino Stack Exchange site is humming along nicely, and it is appropriate here to congratulate Majenko for being the first to reach 20k rep.
Well done.