Last night on NPR's Marketplace  business report, they did a story that I think  was a hoax. They interviewed people who were upset that they bought a house after meeting their nice new neighbors, only to find them gone as soon as they closed on the sale. The "neighbors" were really actors hired by the real estate agent to make it seem like a nice neighborhood to buy in. If it was a hoax (they've done them before), it was beautifully done (right up there with the BBC Spaghetti Harvest), and will fool a lot of people.

Add: Scientific American  magazine has a long tradition of slipping an April Fools joke into its April issue, as an editorial or even an article. Discover magazine used to do the same thing; I don't know if they still do (it's been years since I subscribed).

Update 4/7: Tonight's Marketplace  reported that they were flooded with calls and letters of outrage how realtors could pull such an underhanded stunt -- and that it was  in fact their April Fool's joke. There was also another segment, a perfectly honest and straightforward commentary on some aspect of the economy, that had some people thinking it  was the joke.