Dogtrousers
Kilometre nibbler
In the late 80's we had one of those. Had a catchy name, I've forgotten.
About 5 people used it. Maybe 1 of them understood it.
You could create an email and send it to a fax machine.
We also had a phone system you could dial into almost anywhere and call colleagues within the company.
Some wag discovered that you could call your desk phone, enable call forward and phone outside the company.
I've worked with two. One was in the early/mid 80s and it was an international bank. Part of my job was ensuring that executives had access to their mail, which meant I got to go to fancy conferences and the like - armed with a suitcase of modems, acoustic couplers and so on.
The second was in the late 80s and it was a smaller company. The email system was written entirely by a bloke with frizzy hair and no social skills. It was very quirky.