When director Wes Craven first began work on Scream, one of the challenges he and his production team had to address was how the masked killer/horror movie pop quiz conductor would look. In Kevin Williamson's screenplay, the villain was simply referred to as "ghost mask killer," and there were no further descriptions to go on. Craven and company could've certainly designed a mask that would be frighteningly effective on screen, but it turns out they didn't have to.
While scouting for the film in Santa Rosa, Calif., producer Marianne Maddalena found an abandoned house (that had, coincidentally, been used for Alfred Hitchcock's 1943 thriller Shadow of a Doubt) and explored it as a possible location. The house didn't make it into the film, but while there Maddalena came across a mask that had enough of an impact on her that she decided to show it to Craven. The director loved the find and wanted to use it for the film. That's where the production hit a bit of a snag.
The mask was part of the "Fantastic Faces" line released by Halloween company Fun World in 1992, and Fun World still owned the rights to the look. If Craven wanted it in his film, Dimension Studios would have to pay to license the mask from Fun World, and the mask company wasn't about to give up their license to a major motion picture for peanuts. Rather than pay Fun World to use their mask, Dimension asked Craven to design something similar, but not so similar that they'd be sued. For that, the director turned to effects gurus Greg Nicotero and Howard Berger of KNB Effects, who designed a new, non-copyright-infringing version of the mask.
So Craven began shooting with the KNB mask, but Dimension may have simply demanded the mask be changed as a negotiation tactic. While the film was still in production, Dimension and Fun World came to agreement that allowed Craven to use the original mask in the film. Scream was a huge, franchise-spawning hit that revitalized the slasher genre, and the "Ghostface" mask was ingrained in pop culture forever. After it hit the big screen, the mask made a ton of money for Fun World, and you can still find it in the Halloween aisle at your local grocery store to this day.
For more little-known (sci-fi, mostly) facts, just click the tag.