Way back, when I worked for the UK bit of AT&T we had e-mail addresses that were in the format !name (i.e. an exclamation mark at the front - although they called it a "bang" )
It was an internal e-mail BUT somehow linked to the outside world's, then, primitive e-mail network ... I can recall having in 1993 an early clamshell notebook PC (an AT&T Safari ... made, I think, by NCR) - with a modem that plugged in and ran at about 300baud on a dial up - with a mono screen of course. Those were the days!
Rob
You needed to give path from some well known node, so you'd see addresses along the lines of ...!ucbvax!uc4!uel!quaduk!person
We probably know a few people in common as back then I used to do a lot of work with AT&T in the UK, mostly with USL.
I have such a great email address that I get email most weeks asking if they can have an address in the domain, to which I have to tell them that if they can't prove that they know what V7 is and why HoneyDanber was a great step forwards then they go away.