You have to at least give Joaquin Phoenix and Casey Affleck an A for effort. For two years, Phoenix's bizarre public behavior, chronicled by brother-in-law Affleck in the actor-turned-director's film 'I'm Still Here,' left observers guessing as to whether they weren't witnessing some kind of epic celebrity meltdown. It couldn't just have been a Method-acting stunt, could it? Because who could remain committed to a course of public self-sabotage for that long?

Alas, it was less than a week after the release of 'I'm Still Here' that Affleck admitted that, yes, the whole thing was a hoax, a grand act of performance art on Phoenix's part. And the revelations keep coming. (The latest: David Letterman, whose train-wreck February 2009 interview with a shaggy, dazed Phoenix appeared to mark the start of the actor's epic slide, was in on the hoax from the beginning, despite an earlier denial from Affleck.)

I'm Still HereIt's too bad Affleck spilled the beans so quickly, since viewers and critics could have spent weeks or months debating whether or not the film was an unfathomably meticulous put-on or a horrifying true document. Which is why it's not clear whether or not 'I'm Still Here' belongs in the pantheon of classic movie hoaxes. After all, some of the frauds on the list fooled people for months or even years before they were exposed. True, Phoenix's eccentric I'm-giving-up-film-for-hip-hop act fooled people for a couple years, but the movie was barely in theaters before Affleck's admission rendered it anticlimactic. Still, for a long time, Affleck and Phoenix's commitment to deceiving the world, at Phoenix's expense, was total. You have to give them that.

Read the list of great movie hoaxes below and decide for yourself whether 'I'm Still Here' belongs in their august, fraudulent company.

'The Broken Oath' (1910)
Florence Lawrence was not only the first movie star; she was the first to participate in a publicity stunt, one that capped one of the most brazen movie hoaxes ever. In those pre-Hollywood days, there was no star system, and even actresses with familiar faces, like the prolific Lawrence, were largely anonymous (she was known merely as "the Biograph girl," after the studio she worked for). When Independent Motion Picture Company chief Carl Laemmle hired her, he decided to make her a household name by killing her off. He planted a story in newspapers that she'd died in a trolley accident. Speculation about her mysterious death escalated for weeks until IMP placed a large advertisement revealing that Lawrence was still alive and falsely blaming rival Biograph for the original fake death story. In fact, the ad stated, Lawrence had just finished filming a picture called 'The Broken Oath' (but the ad accidentally swapped an O for a B, mislabeling the movie as 'The Broken Bath'). To promote the movie (and prove she was still alive), Lawrence made a personal appearance in St. Louis and was mobbed. The stunt worked, maybe too well. Laemmle (who would go on to found Universal) had inadvertently invented the star system, fueled by gossip and lies, that still exists today, and had begun the shift of bargaining power from the moguls to the actors.

'Snuff' (1976)
The urban legend behind so-called "snuff films" -- films which supposedly show actual on-camera murders -- begins here. Actually, it begins with a low-budget 1971 exploitation film called 'Slaughter' that was inspired by the Manson killings and was barely released (and not to be confused with the 1972 hit starring Jim Brown). Producer Allen Shackleton appended a realistic murder scene onto the end and (without the knowledge or consent of the original 'Slaughter' filmmakers) re-released the film as 'Snuff' in 1976. To promote the idea that the killing was real, he invented fake protest groups to complain to newspapers about the film and stage rallies outside theaters showing it. The trick worked too well. Not only did it make 'Snuff' a minor hit, but it also convinced people that there really was such a thing as snuff films, paving the way for similar hoaxes like 1978's 'Faces of Death,' a purported compilation of snuff footage. (Actually, some of the 'Faces' deaths were real, consisting of newsreel footage of wartime carnage, but its original footage was all faked.) 'Faces,' in turn, spawned numerous sequels and an urban legend that wouldn't die.

'Cannibal Holocaust' (1980)
Italian director Ruggero Deodato took the snuff craze to the next level with this film, which purported to contain found footage made by an American film crew that depicted the filmmakers themselves being killed and eaten by Indians in the Amazon. Adding to the illusion were the actual on-camera slaughters of several animals and the disappearance from the public eye of the actors playing the slain filmmakers. (Deodato had signed them to a confidentiality agreement requiring them to keep a low profile for a year after the film's release.) The film was so convincing that Italian authorities arrested Deodato for murder. To prove his innocence, he released the actors from their contract and gathered them together on an Italian TV show, and he had them demonstrate how some of the gorier effects depicting their own torture and murder were faked. Still, the film was banned in Italy for years over its scenes of animal cruelty.

'Universal Soldier' (1992)
On the red carpet at the Cannes Film Festival, Jean-Claude Van Damme and Dolph Lundgren bumped into each other and got into a fight that appeared in paparazzi photos around the world. Lundgren later admitted on his website that the scuffle between him and the Muscles from Brussels was a publicity stunt, a staged "Mohammed Ali/Joe Fraizer [sic] moment," meant to drum up interest in the pair's new action flick.

'Alien Autopsy'
At the height of the 'X-Files' era, this black-and-white short film became a worldwide television hit. British filmmaker Ray Santilli claimed the 17-minute film had been spirited away from U.S. government authorities and showed the dissection of an actual alien corpse recovered in the fabled 1947 UFO crash in Roswell, N.M. When it aired as a special on Fox in 1995, Santilli's footage was surrounded by commentary by Hollywood make-up artists, pathologists and other experts debating the authenticity of the footage. Not until 2006 did Santilli admit that the film was fake, though he continued to claim it was a re-enactment of an alien autopsy film he'd actually seen. The original film, he said, had all but disintegrated, though he'd saved a few frames and spliced them into his own movie. So his film was really a restoration, he claimed, albeit one in which he had to recreate most of the original from scratch.

'Dadetown' (1996)
Director Russ Hexter called this portrait of social and economic upheaval in small-town America a "meta-documentary." In a style familiar to viewers of PBS documentaries, 'Dadetown' depicted a factory town in upstate New York where blue-collar jobs were disappearing, even as white-collar workers were moving in to work at a new software company and displacing longtime residents. The film showed how tension between the tradition-minded locals and their new yuppie neighbors ultimately erupted into violence. It also showed, if you watched all the way to the end credits, that the entire film was a fake, a fictional story acted out convincingly by unfamiliar performers in front of a realistically fly-on-the-wall camera crew. Many reviewers were careful not to spoil the film's secret, but some viewers felt duped. At the movie's Vancouver premiere, a woman told Hexter, "I think you're going to do great in Hollywood because you're a liar and a cheat." Unfortunately, he did not; shortly after the release of his only film, Hexter died at 27 of an aortic aneurysm.

'The Blair Witch Project'
This micro-budgeted indie film, shot on shaky video cameras, brought the fake found footage genre into the digital age and all but invented viral marketing. Thanks in large part to a well-crafted Web campaign that seemed to authenticate the film and made people believe the Blair Witch legend was real, this $60,000 film grossed $141 million in theaters. Even after the little-known actors who played the doomed video crew started popping up alive and well on talk shows, the Web lore still convinced many fans that there really was a Blair Witch.

David Manning (2000-01)
Some critics whose names you see over and over in the blurbs on movie ads seem suspiciously easy to please. One such critic was David Manning of the Ridgefield Press, who lavished praise on such Sony releases as 'The Patriot,' 'Hollow Man' ("One helluva scary ride! The summer's best special effects."), 'Vertical Limit,' 'A Knight's Tale,' and the Rob Schneider comedy 'The Animal' ("Another winner!") As it turned out, Manning didn't exist; his blurbs were a creation of Sony's marketing department. When the deception was revealed, two Sony marketing executives were sacked, and the studio was fined for deceptive advertising by the state of Connecticut (the home state of the real Ridgefield Press). Facing a class-action suit filed in California over the fake critic's praise, Sony defended itself on free speech grounds, a defense the judge called frivolous. Ultimately, the studio set aside a $1.5 million fund to refund $5 to every dissatisfied customer -- or at least every dissatisfied customer who was willing to admit they'd paid to see a Rob Schneider comedy based on the endorsement of a critic whose reviews they'd never read.

'Borat: Cultural Learnings of America for Make Benefit Glorious Nation of Kazakhstan' (2006)
The many fooled by the disingenuous Kazakh journalist must not have watched much HBO, or they'd have recognized that Borat Sagdiyev wasn't really a naive documentarian with perverse, barbaric personal habits, but rather a British comic actor named Sacha Baron Cohen who'd created the Borat character on his 'Da Ali G Show.' Of course, Baron Cohen's project depended on the people he filmed himself interacting with not being in on the joke. The finished film was a mercilessly funny satire on American life, in which the various experts and laymen Borat filmed during his supposed chronicle of American manners often proved to be just as unsavory, sexist, homophobic and anti-Semitic as Borat himself. 'Borat was also a big box office hit and the catalyst for numerous lawsuits against Baron Cohen and the other filmmakers by people they'd filmed who claimed they felt defrauded and defamed. (This even though they'd signed releases when they agreed to appear in the supposed documentary.) The film was also banned in Kazakhstan and most of the Arab world. Baron Cohen tried the same trick again for 'Bruno,' once again going undercover as one of his 'Ali G Show' characters, but by then, his idiot-provocateur shtick had run thin.

•Follow Gary Susman on Twitter @garysusman.