* The voice of Gozer was provided by an uncredited Paddi Edwards.
* The voice of Zuul was provided by an uncredited Ivan Reitman -- the director of the film himself.
* The girl with the pink bow in her hair, celebrating her birthday at the Tavern on the Green is singer Debbie Gibson.
* One of the people in the crowd looking on as the containment unit explodes is adult film legend Ron Jeremy.
* Charles Levin and Wendy Goldman were originally in the film as a couple spending their honeymoon night in the Sedgewick Hotel. Their scene, although deleted from the film, appears amongst the deleted scenes on the GB1 DVD.
* Two frequently-used (perhaps over-used) "famous" sound effects are heard in the movie: The Universal Telephone Ring and Castle Thunder. The Universal Telephone Ring can be heard coming from Dana's phone (with a different pitch) just before she's dragged into the kitchen (DVD time code 50:31). Castle Thunder can he heard at least two times: when we first see the statues on the rooftop after the "twinkie" speech (DVD time code 48:42), and when Dana and Louis are transforming into the Terror Dogs (DVD time code 84:12). It can probably be heard a few more times during the rooftop scenes. (The original sound effects audio files were provided by Steve Lee, from the two pages linked, converted from wav to mp3 by me. The GB1 audio files were recorded by me.)
* The Ghostbusters phone number is (212) 555-2368.
* Production designer John De Cuir said the temple set was the most expensive and technical set ever constructed. Dan Aykroyd called it, "... your average Pre-Sumerian temple."
* After the film was out and doing well - just to keep the phenomenon going - Ivan Reitman came up with the idea of taking a "junk buy" cross-country on late-night TV and running the commercial just as it appeared in the film, with the superimposed phone number changed to an 800 number. Then people could call in and get an answering machine with Dan Aykroyd and Bill Murray's voices saying: "Hi, we're the Ghostbusters. We're not in right now - we're out catching ghosts ..." Well, they did that, and they got a thousand calls per hours, 24 hours a day for six weeks.
* The set used in the hallway sequences of the Sedgewick Hotel were originally built for and used in the film "Rich And Famous" (1981) and were patterned after the Algonquin Hotel in New York.
* The "Ghostbusters" crew and the crew of the television series "Hill Street Blues" kept running into each other during filming of their respective shows.
* Louis' apartment is actually behind the door that Louis comes out of, and Dana's apartment is actually on the other side of the door she enters - which is unusual in filmmaking.
* Pre-production was well underway before anyone realized that Filmation had produced a short lived Saturday morning children's show called "The Ghost Busters" during the 1975-76 television season. Columbia quickly entered into negotiations with Filmation to secure rights to the title. Through most of the New York location photography, Ivan Reitman and the crew were uncertain as to what their film would eventually be called. At one point, it was going to be called "Ghoststoppers," but Columbia finally struck a deal with Filmation that allowed use of the original title.
* The filmmakers planned to do a second commercial in the film - one that would have been shown after the "Ghost Fever Grips New York" montage. It was going to be an elaborate MTV music video, with the guys singing the "Ghostbusters" song - which they could have actually played on MTV. Unfortunately, they didn't get the song they liked until late in post-production, and by that time it was too late to go back and do it.
* The fictitious magazine covers and newspaper front pages contain pictures of the crew. Time's corner flap bears the image of associate producer Michael Gross, while U.S.A. Today's golf victor is Michael McWillie - a designer hired to produce the bogus covers. Another is Gross' wife.
* The scene in which the wall blows off in front of Sigourney Weaver was actually shot live. This shot could have been accomplished using special effects, but Sigourney Weaver loves danger and went for the more authentic shot.
* The sprawling apartment interiors - two key apartments and the hallway between them - extended over two adjoining sound-stages on the Burbank Studios lot.
* The "Ghost Fever Grips New York" montage was shot in one day, with a small crew quickly moving from location to location with no permits to shoot in any of the locations. Dan Aykroyd was really driving Ecto-1.
* The film's theatrical teaser features a song called "Ghostbusters," which is completely different from the Ray Parker Jr. song.
* The librarian was originally to be in her late 20s.
* When the script was finished some months, Dan Aykroyd submitted it to Ivan Reitman -- complete with conceptual illustrations and a quickie videotape of himself in a jumpsuit-based uniform embellished with makeshift nutrona wands and a proton pack fashioned from styrofoam and old radio parts.
* The stacks in the Los Angeles Public Library doubled for those in the New York Public Library.
* PKE is an unexplained acronym for "psycho-kinetic energy." Dan Aykroyd was responsible for most of the film's specialized jargon.
* Although permission was granted for the production unit to shoot on the Columbia University campus, it was with the understanding that the school not be identified as such in the film. Neither Weaver Hall nor a "Paranormal Studies Laboratory" actually exists at Columbia. Though the interiors could just as easily have been shot on a soundstage back in Los Angeles, a university building was dressed as a lab set by production designer John DeCuir as a hedge against inclement weather, Thus, if the location film crew -- which cost about $200,000 a day to maintain -- was unable to shoot outdoors, they could readily proceed with the lab scenes rather than lose a day in the schedule.
* At one point, another scene was to follow Dana's departure from her kitchen. As soon as she left the kitchen, every metal appliance and utensil in sight was to fly across the room and stick to the refrigerator door, After discussing numerous ways to achieve the effect -- the most likely being attaching the implements to the refrigerator and then yanking them away with invisible wires as the camera recorded the action in reverse -- the idea was discarded as unnecessarily difficult.
* The Sedgewick Hotel hotel exteriors and the inside lobby scenes were shot at the Biltmore Hotel in downtown Los Angeles. The original plan was to shoot the hotel scenes on location in New York. One of the spots we considered was the Waldorf Astoria, but their lobby area was too small. The Biltmore's lobby is huge -- which, allowed Ivan to do a great tracking shot of the Ghostbusters entering the hotel.
* Though the Sedgewick Hotel hallway scenes were filmed on a soundstage, the Ballroom sequence was shot at the Biltmore Hotel. Modified with a breakaway chandelier and a set of prefabricated replacement walls, the ornate banquet facility was taken over by the film crew and occupied for two days.
* Casey Kasem was included at the very last minute during postproduction. In fact, the idea of putting him in came to the filmmakers the day before his lines were recorded. They called him up, made the deal, he appeared the next day, read his bit and they cut it into the film -- all in 24 hours.
* For the long shots at Lincoln Center, the filmmakers had to loop the dialogue because the fountain in the background created so much noise. For the closeups -- when the fountain was out of frame -- they were able to have the water shut off.
* The original idea was for Louis to be trapped by the Terror Dog in a dark corner of Central Park.
* Because shooting time ran out in New York, Venkman's entrance into Dana's apartment house was not shot at the 55 Central Park West location -- but rather at a facsimile of its ground floor constructed at the Columbia Ranch in Burbank for the later sinkhole sequence. Rather than go to the expense of bringing the New York "doorman" to Los Angeles, a different, but similar-looking actor was hired for the pickup scene.
* The scene where Winston and Ray discuss the Bible and Judgment Day was the scene the filmmakers used to audition actors for the role of Winston.
* The Fort Detmerring exterior set was a standing set at the Columbia Ranch, dressed rather simply with an identifying sign and a guard shack.
* The Single Officers' Quarters at Fort Detmerring, where Ray has his encounter with the Dream Ghost, is really a small set adjacent to Dana's apartment on Stage 12.
* The incarceration scene was shot on location at an actual New York prison facility, now out of commission and essentially abandoned. The lock-up was just a terrible place to shoot. It was dark and very crowded, with low ceilings and dirt everywhere. Dan Aykroyd said, when they were shooting there, "If there are ghosts anywhere, they would be here." Later, they discovered scratches in the film that was shot that day, and they were all afraid they'd have to go back there to redo the scene. Fortunately, Sheldon Kahn was able to work around the scratches in editing and the reshoot wasn't necessary.
* The office of City Council president Carol Bellamy was graciously made available as a stand-in for the actual mayor's office.
* In the film, after Peck charges the Ghostbusters with fraudulently staging the psychic disturbances, Stantz proclaims: "Everything was fine with our system until the power grid was shut off by dickless here." When Peck responds by accusing them of causing the explosion, the mayor asks, "Is this true?" Venkman promptly replies: "Yes, it's true. This man has no dick." Peck lunges wildly at Venkman, and only after several frantic moments is calm restored to the office. "Well, that's what I heard," Venkman adds quietly. There were several variations of that scene on the set. During one take, Danny called Peck "wee wienie winkle" and Bill Murray broke up completely -- which is something he almost never does on camera.
* The loading dock at the rear of City Hall is actually a building across the street from the Real City Hall, since the Real City Hall has no loading dock.
* The melted marshmallow that falls on Walter Peck is really two hundred pounds of shaving cream that was released from a giant plastic bag attached to a crane high above Peck.
* Originally, they were going to have the Terror Dogs simply transform back into Dana and Louis -- just like the first transformation. But Ivan came up with the idea of charred bodies that could be chipped away, revealing Dana and Louis inside. It was a much more imaginative way to bring them back and it created some suspense because, for a moment, Venkman and the audience think that Dana is dead.
* When the GBs enter the Sedgewick Hotel, if you look carefully at the stores across the street in the background, you'll notice that one of the stores is named "Biltmore Hotel Cleaners." The hotel that is doubling for the Sedgewick in the film is the Biltmore Hotel in California. It should be noted that, based on other films (such as 1994's "Dave"), there doesn't appear to be any stores or store fronts across from that entrance of the Biltmore Hotel. So, I assume that the store fronts seen in GB1 are fake, and the use of the words "Biltmore Hotel" on the cleaning store is the filmakers way of paying homage to the hotel in which the movie was filmed.
* The firehouse which was to become the Ghostbusters' headquarters was, in reality, two separate buildings -- 3000 miles apart. All of the exterior shots were filmed at an old firehouse in New York, which is still in use, while the interiors were shot in a decommissioned firehouse in Los Angeles, presently employed as an artist's studio, The two buildings were remarkably similar, both in appearance and layout.
* The character of "Louis Tully" was originally to be played by John Candy.
* It was Rick Moranis' idea that Louis Tully be an accountant.
* A 1959 Cadillac Miller-Meteor limo style ambulance/hearse combo was converted into Ecto-1.
* The role of Peter Venkman was originally scripted for John Belushi.
* Gozer is based on several things. For one, there's a Gozer Chevrolet dealership in upstate New York. A little more to the point is the fact that Gozer was a name that related to a documented haunting in England -- the one "Poltergeist" (1982) was based on. During this particular haunting, the name Gozer appeared mysteriously throughout the house, written on walls and things.
* Due to Slavitza Jovan's Slavic accent, the voice of Gozer was dubbed by Paddi Edwards. Bill Murray did a hilarious take of a scene, playing off the fact that the actress had an accent. When Gozer says, "Choose and perish," Bill responded: "Jews and berries? I don't understand."
* As originally conceived, Gozer was to have been a rather non-descript, kindly looking man.
* Originally, the Stay-Puft marshmallow man was to rise up out of the river, right by the Statue of Liberty.
* A large billboard appears on a building near the Ghostbusters firehouse. Featured on it is a picture of the Stay-Puft Marshmallow Man and the words "Stay Puft Marshmallows - Stay Puft, Even When Toasted" - an advertising slogan from Dan Aykroyd's original script.
* An early idea was to have the Marshmallow Man change into a third, large manifestation of Gozer, instead of dying.
* The Stay-Puft Marshmallow Man appears several times in the film because the filmmakers wanted to build a continuity of his presence. He can be glimpsed on a billboard and on a package of Stay-Puft marshmallows that Dana buys.
* One group within the production crew wanted him to be 100 feet tall, and another wanted him to be 125 feet. Ivan Reitman settled the arguement by making him 112 1/2 feet tall. In the film, he's mentioned at being 100 feet tall.
* The filmmakers were concerned that Stay-Puft would take the movie into an area of silliness that would just discount everything else. All through the writing process and production, they were trying to come up with an alternative, but they just kept coming back to Stay-Puft.
* The filmmakers considered either ending or beginning the Ghostbusters commercial with a Stay-Puft spot - complete with a little stop motion Marshmallow Man dancing around the countertop like the Pillsbury doughboy. They disgarded the idea as being a bit of overkill.
* In the original script, the Marshmallow Man was pretty much a throwaway - just another effect. But it was such a great image that it was decided to use it as the manifestation of Gozer.
* Although never specifically named in the film, the hotel apparition was to become known within the production unit as the Onionhead ghost - so dubbed because of the horrible stench which emanated from it, rather than from any physical resemblance to an onion. Though the malodorous aspect of the creature was dropped when the newlywed scene was cut - primarily because to visually support the notion would have required massive amounts of exacting, hand-rendered animation during the postproduction effects phase - the name "Onionhead" persisted among members of the crew.
* The hotel apparition made a special reappearance at the end of Ghostbusters, which many misinterpreted as implying a sequel.
* Vinz Clortho and Zuul appear in the form of male and female Terror Dogs. The only difference between the male and female Terror Dogs is that the male has longer horns.
* Stuart Ziff -- whose shop was responsible for building the Terror Dogs -- was always paranoid whenever his creatures were on the set. He'd had bad experiences on other projects with things being broken and shooting being stopped for repairs, and he was always warning the cast and crew to stay away from them. Once the Terror Dogs were on their pedestals, Stuart was assured that everyone would be kept away. But the first day they were on the set, Bill Murray walked up to one of them -- who's going to tell Bill Murray not to touch the dogs, right? -- and he said, "Gee, this is neat." Then he reached out and petted it on the head -- and almost as if on cue, one of the horns fell off, dropped to the floor and shattered.
* In early drafts of the script, the Terror Dogs were sympathetic creatures from another dimension, who were terrified of Gozer and were trying to escape him. They took the form of human beings and went to the Ghostbusters seeking help.
* The Ghostbusters logo was refined by artists, but Dan Aykroyd created the idea for the logo when he dreamed up the original concept for the film.
* The library ghost was a mechanical puppet. An even more ferocious version was created and rejected but it did appear in another film, "Fright Night" (1985?).
* The original concept for Winston's character was younger and hipper. At one point, the producers were talking with Gregory Hines about playing the part. They also considered getting a young black comedian -- someone like Eddie Murphy.
* Remember the shot in the film where the Ghostbusters look out of Dana's blown-out apartment and the camera pulls way back revealing the entire apartment building? Well, if you didn't already know, all of the area surrounding the Ghostbusters, including the building itself, is a matte painting. This is why the cars on the streets aren't moving. Well, if you look closely at the balcony on an adjacent building in the lower right corner of the screen when the camera starts to pull WAY back, you'll see some people moving. Those people are Matthew Yuricich (Chief Matte Artist), Michelle Moen (Matte Artist), and a few others. They were photographed in order to give the shot a little more movement (and prehaps as an inside joke, as well).
* When you see Slimer flying around the chandilier in the Sedgewick Hotel's ballroom, what you are really seeing is a peanut that was spray painted green -- so says Terry Windell (the animation supervisor).
* Pee-Wee Herman and Grace Jones were originally considered to play Gozer, and the role was originally offered to Anna Carlisle (a punk rocker). The role of Janine Melnitz was originally offered to Sandra Bernhardt.
* The symmetrical book stacking scene was thought up by Ivan Reitman as he was going to the set the morning the scene was shot. The dialogue was quickly written.
* The crew originally wanted to shoot the hotel lobby scene at the Waldorf Astoria in New York City, but chose instead to shoot it at the Biltmore Hotel in Los Angeles because of it's huge lobby.