Hackers Delight, The Term Originated in the Miniature Train Community for Taking Something Apart to See How It Works. Quite a Lot Started that Way. Next Came "Black Boxes" Tools to Use the Analog Switches at Ma Bell/AT&T to Make Free Calls by Mimicking the Correct Tones. I Learned Quite Early working with AUTOVON to Mimic the Tone to Up the Precedence of My Call Just by Whistling. Did it Every Time I Called My Detailer.