So then @paulrickards and I were playing around trying to get our networks talking to each other.
After a couple of false starts, it turns out oldsk00l IP stuff *really* doesn't like any kind of NAT malarky, and I'm currently trapped behind carrier-level NAT that I can't do anything about.
So Paul did some digging and managed to whip up some sort of magic Python UDP tunnel and we've somehow managed to print to each other's ImageWriters across the Atlantic :D