You can see them from miles away, slowly materializing out of the ozone when you travel toward them on I-35W or 694 on a clear day, and the red safety lights pulsing through clouds or fog or the night sky.
I was making improvements to the local inter-user mail program called SNDMSG. Single-computer electronic mail had existed since at least the early 1960’s and SNDMSG was an example of that. SNDMSG allowed a user to compose, address, and send a message to other users’ mailboxes.