On Halloween a few years ago, in the New York State Bar Association Journal, Daniel B. Moar described the case of Stambovsky v. Ackley:

The plaintiff had commenced an action to rescind a real estate purchase after he discovered that the house he bought was possessed by ghosts. Believing that it could not award the buyer a remedy, the trial court dismissed the complaint.

The appellate court disagreed, finding that the “unusual facts . . . clearly warrant a grant of equitable relief to the buyer.” The seller had repeatedly reported to the media the presence of ghosts roaming the house. As a result, the appellate court found that the seller was “estopped to deny their existence and, as a matter of law, the house is haunted.” Additionally … the court noted that even “the most meticulous inspection” would not have discovered their presence and put the buyer on notice.

h/t to Eugene Volokh.