To disguise the third Star Wars movie and to keep it more secretive, George Lucas gave the movie a fake working title while they were filming, He dubbed it Blue Harvest, it was supposed to be a horror movie. Lucas even wrote a tagline for the fake movie; 'Horror beyond imagination.' All of the crew on the Star Wars sets in America wore hats and shirts that said Blue harvest.
Blue Harvest is a parody of Red Harvest, a novel by Dashiell Hammett, A novelist, several of his book's were turned into movies, such as yojimbo, a classic samurai movie.
On the set of Indiana Jones, Steven Spielberg wore a Blue harvest hat.
www.blueharvest.com takes you strait to www.starwars.com
Coolest of all, When The Simpsons Movie came out the reels sent out to the theaters were titled Yellow Harvest.