This is the 60th anniversary of the greatest April Fool's Day joke ever by, of all people, the BBC News division. We studied this incident in my media and journalism courses at Missouri State University, back when it was Southwest Missouri State University. None of our professors had a copy of it. They assumed it was lost (kind of like early Doctor Who episodes). We can see it, thanks to YouTube.
On April 1st, 1957, the BBC news program, Panorama, ran a 3 minute story about the abundant harvest this spring on spaghetti trees in Switzerland. It was narrated by the shows, usually serious host Richard Dimbleby. At the time, spaghetti and pasta were not foods that the British ate. The only way to get spaghetti, in the 1950s, in Great Britain was pre-cooked in a can with tomato sauce. People began calling the BBC to find out if they could grow it in their back yard.
Here is the full report. The only thing missing from this is Richard Dimbleby's tag at the end, saying into the camera, "And that is our program for today, April 1st, 1957."
Runners up on great April Fool's Day jokes would be when a reporter for an NBC affiliate in Missouri (John Pertzborn, I think), in the early 90s, profiled a couple that was receiving "left over" TV transmissions from the 1950s. I became suspect when it seemed everything they were watching was off at Goodtimes or Video Steve compilation tape. Another April Fool's joke in the Missouri media world was in the late 80s, when the then top rated Top 40 radio station in Springfield, Missouri, KWTO-FM Rock 99, announced it was going country and the DJs quit on-air. Also a few years ago, Northern Bath Tissue announced their "Rustic Weave Artisan Toilet Paper" in an online commercial (I love the look on that woman's face when she sits down). Also, comic fans used to laugh about the time Comic Shop News announced that D.C Comics had bought out Marvel Comics. This was before Warner Brothers bought out D.C and Marvel was bought out by Disney.
Happy April Fool's Day!