It also introduced "This Is Spinal Tap," a mockumentary about an unsuccessful American tour by the fictional British band Spinal Tap featuring actors Christopher Guest, Harry Shearer and Michael McKean, who played guitarist Nigel Tufnel, bassist Derek Smalls and lead singer David St. Hubbins, respectively.
The other films made a lot more money than "Spinal Tap," but the band that would be a heavy metal legend lives on as a cult movie classic.
Now, 27 years later, Spinal Tap is being honored with its own holiday: "Nigel Tufnel Day," which takes place one day only: Nov. 11, 2011 -- or 11/11/11.
Not familiar with the film or the reference to 11? Well, at one moment of the movie, the very dimwitted Tufnel shows off his amps and their dials that are numbered up to 11, a notch higher than typical 1-to-10 amps. They're superior because, after all, "11 is one louder than 10," Tufnel said.
The "holidate" is the brainchild of former musician and Spinal Tap fan Michael Fennelly, who decided last year that Nov. 11, 2011, should honor his favorite flick.
WATCH: THE CLASSIC SPINAL TAP MOMENT:
"There is a certain beauty to the perfect stupidity of Spinal Tap," said Fennelly, who has sung with groups like Steely Dan and Crabby Appleton, which had a top 40 hit in the 1970s with "Go Back." "So much of what happens in the movie is true that many musicians feel pangs while watching it because basically your whole career is mocked."
He isn't kidding. Some of the musicians who've reportedly cried, not laughed, while watching the movie, include The Edge, Eddie Van Halen and Tom Waits.
Fennelly's Facebook page on 11/11/11 attracted more than 12,000 fans in the first couple of days after posting it on Nov. 5, 2010. "It tapered off for a while, but we've been getting more attention since mid-October. I told people we can't wait for the eleventh hour, but that's exactly what happened."
Fennelly's plans for Nigel Tufnel Day are relatively mellow. He plans to follow on the action on his Facebook page and try and find a Skype interview that Shearer and Guest are having after a screening of "This Is Spinal Tap" at the Brooklyn Academy of Music.
"As far as I know, that's the extent of the activities of any of us regarding this occasion," Shearer told HuffPost Weird News via email.
Meanwhile, musician Adam Gimbel, who created a separate Facebook page that taps into the various Tufnel Day celebrations, said at least 40 Spinal Tap celebrations are on tap, including shows in England, Ireland, Norway and France.
Gimbel is also getting into the act himself. His Spinal Tap tribute band, called Twelve, will be performing a set of 11 Spinal Tap songs at a San Diego club called, not coincidentally, Bar Eleven.
"I made sure to get the day back in February, just to make sure," he said. "We will be starting at 11:11 p.m."
Although Gimbel will be singing most of the Spinal Tap songs dressed up as David St. Hubbins, the spotlight will undoubtedly be focused on guitarist Jeff Musser, who will be playing Tufnel.
He's been spending his waking hours learning Tufnel's trademark guitar wizardry, including strumming with his shoe and playing another guitar with a violin -- not the bow, which is Led Zeppelin guitarist Jimmy Page's trademark.
"Actually, the hardest song will be 'Stonehenge,' because I have to sing and play and capture the eerieness of Stonehenge," said Musser, who promised HuffPost Weird News that Twelve will include an 18-inch model of Stonehenge during the number, just like in the movie.
"Oh, and there will be druids dancing around it," he added. "You have to have those."
Not all Tufnel Day galas will occur in musical settings, but at least one software company is amped up for the big day as well.
It's called, appropriately enough for the day, OneLouder, and specializes in making apps for a variety of uses. President Evan Conway said the now-infamous movie scene directly inspired the company.
"Most of us are musicians and that scene just sticks out," Conway said. "We've joked about 11/11/11 day for 10 years, but we prefer to call it 'One Louder Day.'"
For the record, Fennelly is considered to be making the first public declaration of Nigel Tufnel Day -- or, if you have money invested in a certain app company, "OneLouder Day."
Conway said employees in Silicon Valley, Dallas and the Kansas City headquarters will celebrate by dressing up in their best heavy metal outfits.
"I think the cocktails will be flowing around 11 a.m.," Conway admitted. "We'll be tweeting quotes from the movie every hour and will be giving away copies of the movie."
Oh, and they'll be giving away one armadillo, a reference to a line in the movie where Tufnel explains the collective sexual prowess of the band by saying, "We've got armadillos in our trousers. It's really quite frightening."
Conway, a former musician himself, thinks the reason why Nigel Tufnel Day is striking such a chord with thousands of people has to do with the fact that the movie never totally became mainstream.
"It's still a bit of an inside joke," he said. "People in Silicon Valley thought it was a cool name, but didn't get the reference."