The relative time period of Mystery Science Theater 3000. It's supposed to be the future. Exactly when in the future is vague, except to say that it's in the "not-too-distant future". In seasons 1-5, it was called "Next Sunday, A.D."

Next Sunday, A.D. works fine until season 8, where it supposedly takes place a few hundred years in the future. To complicate matters, they then manage to travel back in time to the Roman era, and finally end up relatively in the same time period as they started, which is STILL only known as the not-too-distant future.