It's a way to get into the Subscribed forum--very seldom used. Thing is, you have to be a member for 90 days (I think) and you have to put those words exactly in the title bar and in the message body...with nothing else..no smiley faces, no capital letters...just "subscribe linemen" (without the quotes) in the title and in the text. Pretty funny watching everybody butcher it all to hell trying.
This is CABL.com posting #161096. Tiny Link: cabl.co/mP4u