I can remember a Radio talker by the name of Mark Scott in Detroit area who talked about Echelon back in the early 90’s. I’m sure it’s still in operation and it was keyed to certain words used in conversation.
When I was in school, we had “F ECHELON day”. There was an email that had all of the supposed key words in it, and we forwarded it to all of our friends.
Kind of stupid in a way, but drunk engineers do odd things.