A lot of people think the famous H.G. Wells War of the Worlds Martian invasion was a prank, but it wasn't.
Another popular radio show that aired at the same time, had technical difficulties. Everyone changed their station and came upon the War of the Worlds broadcast right at the most inopportune time.
Can't blame them a bit, especially for that time period, but it's still classic and funny.
I don't think that's quite right. It wasn't "technical difficulties" but a commercial break that made thousands of listeners switch from the other station to Well's broadcast just as the "news reporter" was describing the astounding sight of giant machines coming up out of the ground & attacking people, only to have the "report" then abruptly cut off, followed by 15 seconds of silence. And Orson Wells knew *exactly* what he was doing. He was media-savy to a degree unheard of in that era, and he knew that the first half of his Mercury Radio Theatre program always had much fewer listeners than the second half because the first half was up against the highest rated show of the day, Edgar Bergen & Charlie McCarthy (exactly how they measured ratings back then, and how a ventriloquist act managed to be the most popular show on *radio*, are two things I've never been able to quite figure out). Wells also surmised that, since so many "Charlie McCarthy" listeners tuned to his show once "Charlie McCarthy" was over, that many of them were probably tuning in during the commercial breaks for a quick look (well..., listen) as well, so he very deliberately timed the dramatic moment of the realistic-sounding "news report" suddenly being cut off with 15 seconds of silence to coincide with the first major commercial break of "Edger Bergen & Charlie McCarthy".
So even though there actually were several warnings during the broadcast that what listeners were hearing was fictional (all of them coming while the other station was *not* in commercial break), and the second half of the story was not even presented as a fake news report but rather in the form of a conventional radio play, I still think it has to count as a deliberate, pre-meditated "prank" by Wells.
All this week on Countdown with Keith Olbermen, they've been playing a short, blurry video clip over & over that they found on the "internets" (as Keith calls it for some reason), reportedly of Italian Prime Minister (or something) Berlisconi walking from a building to his limousine and on the way doing something extremely rude, offensive, and hilarious to a meter maid minding her own business. All week long they made certain to mention that they "could not independently verify" that this was the Italian prime minister, in fact they said it so often that it started to seem downright suspicious, then finally on Friday they "sheepishly" admitted that they had just now "discovered" that the clip *is* a fake, it's a scene from a fictional German Mockumentary about Berlisconi featuring a Berlisconi look-alike. Olbermen insists that they really didn't know for certain until Friday that the clip wasn't real, but with an almost literal wink and a nod. Left unanswered in all this is what, exactly, the Germans are doing making scathing, misleadingly realistic, slanderous Mockumentaries about the Italian heads of state up for re-election, and then allowing attributed clips of to show up on the Internets, in what seems to be a deliberate effort designed to turn him into such a laughingstock that he's driven from office. If you ask me, the Germans are definitely up to no good again.