[DrScump]

My first wasn't accessible from public Internet (defense contractor).

My second started in 1986, well before we had domain addressing, so a sender had to know 1) our corporate hostname, 2) my username, and 3) a well-known host to route through (like uunet, pyramid, decwrl, etc.)

The convention for publishing my address, therefore, was

  {pyramid|uunet|decwrl}!infmx!aland

I was actually the first person in the company to put my email address on my business cards! I still have some from then.