Once, during a song intro on KOOL, my radio station of the '80s that only existed on cassettes, I ad-libbed, "KOOL 105 FM, giving you a free music weekend..." It just sounded like the right thing to say over the intro of "Takin' It To The Streets" by The Doobie Brothers.
I never followed up on that premise, though. I didn't pretend to award any free albums or announce any fictitious contest winners. My radio show that day was only 45 minutes long because that was the length of one cassette side. I reasoned that the contest took place during the remainder of the hour that wasn't on tape. In my mind, the show kept going, even after I finished taping it.
That's the beauty of creating your own radio station that no one can actually hear. You don't have to follow up on any contests you create.
