The Franchise: Michael Bay's mega-hit trilogy of robot-on-robot porn, based on the Hasbro toy range… which itself had already led to the 1980s animated TV series and its movie spin-off.
The Fandom: On screen, the Transformers are famous for their ability to change. Their fans: the opposite. Most are so fiercely loyal to whatever iteration of the franchise they fell in love with that they loathe all other variations.
Most Amazing Example Of Devotion: Don Murphy, a producer on the Michael Bay trilogy and a Transformers fan in his own right, opened a website to give fandom the right of reply during pre-production of the first film. And boy did they reply.
The Film: Stanley Kubrick takes on Stephen King and takes an already scary story into the realm of existential horror by refusing to give us closure.
The Fandom: The gap between Kubrick's perfectionism and the puzzle-box nature of the Overlook Hotel, with room that seem to move and doors that go nowhere, is manna to people who won't let things lie, creating grounds for endless debate.
Most Amazing Example Of Devotion: Take your pick from any of the theories presented in documentary Room 237 , but our favourite is the one about the moon landings.
The Franchise: Roland Emmerich's 1994 romp was a minor hit, but it wasn't until the concept spun-out into a TV series (and then another, and another) that anybody realised it had become a full-blooded phenomenon.
The Fandom: The usual mix of spin-off novels, conventions and fan sites, with the crucial difference that the Gateworld forum became so authoritative that the TV show's producers stopped updating their own continuity 'Bible' and used the fan-generated one instead.
Most Amazing Example Of Devotion: Some wag working at the real-life Cheyenne Mountain nuclear bunker - the location for the fictional headquarters in Stargate SG-1 - has officially labelled a room as leading to Stargate Command. [In reality, though, it's a broom cupboard.]
Marvel Cinematic Universe
The Franchise: More like several franchises, as Marvel unites Iron Man, Thor, Captain America and the Hulk - with more still to come - under one brand.
The Fandom: Ironically, given the in-fighting amongst the superheroes, the fans seem to be pretty contented, probably because the whole thing caters so well to the spirit of the comic-book world.
Most Amazing Example Of Devotion: With each new film, the chances of making it through a marathon all-nighter alive are getting tougher.
The Wicker Man
The Film: Buried on release (literally, if you believe the legend that material cut from the film was used as landfill under the M4), Robin Hardy's folk horror has become the subject of obsessive love amongst fans.
The Fandom: The obscurity of the film attracts people interested in a challenge, whether that means putting out an album of the soundtrack to searching for deleted scenes - most recently, the rediscovery of the so-called 'Final Cut.'
Most Amazing Example Of Devotion: Academics held a three-day conference in Scotland in 2003 devoted entirely to the film. Imagine how long it would have been had the event been held after the Nic Cage remake.
The Big Lebowski
The Film: Joel and Ethan Coen's slacker comedy was initially undervalued in the wake of their Oscar-winning Fargo , only to become recognised as probably the brothers' most stuffed treasure trove of mad characters and quotable dialogue.
The Fandom: Jeff Bridges' protagonist, the Dude, is a magnet to anybody whose idea of fandom involves getting quietly chilled with their mates. Fan convention Lebowski Fest has been held annually at cities across American since 2002 and includes - inevitably - a night of bowling.
Most Amazing Example Of Devotion: The Church of the Latter-day Dude - aka Dudeism - was founded in 2005 and now has over 130,000 Dudeist Priests.
The Franchise: Five Brits and a token Yank throw out the TV comedy rulebook to create their very own Flying Circus … and then do much the same thing when they make the transition to movies.
The Fandom: Incapable of getting through a conversation without extensive and encyclopaedic quoting of Python dialogue.
Most Amazing Example Of Devotion: Entrepreneur Elon Musk, boss of SpaceX, launched a test capsule into orbit in 2010 with a 'secret payload' of a hunk of cheese. Why? As a tribute to Python 's Cheese Shop sketch, of course.
The Franchise: Gotham City's Caped Crusader has long veered between capers (the 1960s TV show, the Joel Schumacher films) and crusades (the reinventions of Tim Burton and Christopher Nolan). Guess which the fans prefer?
The Fandom: Surprisingly united in their belief that darker is better. The past decade has been one long Nolan love-in, although the downside is that the fans now need an excuse to vent their long-suppressed hatred. And now it's arrived…
Most Amazing Example Of Devotion: The announcement that Ben Affleck is to play Bruce Wayne in Zack Snyder's forthcoming Superman vs Batman film has trumped even the 'Bond is blonde' debacle by prompting nearly 100,000 furious fans to demand he is removed from the role.
The Film: The big-screen spin-off from Joss Whedon's cowboys-in-space series Firefly , no hit but much loved by its loyal fanbase.
The Fandom: Named after the series' resistance fighters, the Browncoats mobilised after the cancellation of Firefly and were instrumental in convincing Fox to greenlight the film.
Most Amazing Example Of Devotion: The extraordinary lengths the Browncoats went to in protest at Firefly's axing, which included taking out an ad in Variety.
The Franchise: Tenuous one, this - the good Doctor (played by Peter Cushing) battled the Daleks in cinemas during the 1960s, but the films don't have fans so much as apologists. All eyes, really, are on the TV series.
The Fandom: Forget the stereotype of the socially awkward bloke wearing a Tom Baker scarf. Doctor Who fandom is notable for how proactive it is - when the series was axed in 1989, the fans wrote novels and directed audios starring past Doctors. Their number included Russell T. Davies and Mark Gatiss, later to come back as showrunner and writer, respectively.
Most Amazing Example Of Devotion: After 50 years of time travelling, it's nigh on impossible to fit every adventure into a coherent timeline. Yet that's exactly what fans Lance Parkin and Lars Pearson have attempted in their epic book, Ahistory .