Inerestingly enough in 1980 I worked for the one (and hopefully only)
company that I hated going to work each day. At the time my (first) wfie and
I had just moved to FLA from NY. All of her friends were in NY. Our
telephone bills were HUGE. Since I hated the company, was young (21) and
rather a loose cannon. I made use of the very technique that spawned this
legend (with minor changes).
I would call my wife at the apartment, ask which friend she wanted to speak
with, initiate a three way with the friend in NY. I would then put my
receiver back on the cradle with a little wedge so you could not see that it
was really off hook. People DID wonder why my extension was always busy....