Jim Henson's unpersuasive '80s Muppet spin-off about a commune of ecologically sound, dreamweaving sock puppets.
Similarities: An isolated race of tufty furbags engaged in a highly complex and evolved societal structure that places symbiotic harmony with Gaia above all. Big Jim Cameron was mad busy in the mid-'80s, but it looks like he still managed to carve out time for a regular fix of Saturday morning TV.
Differences: Chances are ‘Avatar' won't feature an impossibly chipper theme song, a talking compost heap or a vacillating acid-casualty called Wembley, but don't rule out the inclusion of Screaming Iceworms, Singing Cacti or some Moss-billed Flubberducks!
Return of the Jedi
The inspiration behind the Ewoks was George Lucas's desire to show a pre-industrial race opening a can of furry violence on the technologically advanced Imperial stormtroopers.
Similarities: Hirsute, spear-chucking forest-dwellers v body-armoured goosesteppers out to conquer the galaxy.
Differences: Don't expect Toys R Us to be crammed with Naavi dolls this Christmas.
Blue Man Group
'Edgy', body-paint based stand-up for people who think ‘Rent' is a little too outré.
Similarities: Well, they're... blue? That's about it.
Differences: From what we've seen thus far, there's no sense that Cameron is going to sling the gunships aside and have the blue nymph creatures splash poster paint over each other while ‘Stomp'-style drum clattering plays out in the background.
The Word for World is Forest by Ursula Le Guin
Le Guin's hard-hitting, ecologically aware sci-fi novel imagines the (often literal) destruction of an agrarian alien race by human invaders.
Similarities: The idea of pumped-up imperialist jarheads exploiting indigenous peoples for their own gain goes back to the Egyptians, but Le Guin's tree-hugging sci-fi angle, plus the film's arboreal setting, make it an obvious inspiration.
Differences: The dumpy, fur-covered, psychedelically inclined Athsheans are to Jim Cameron's athletic Naavi what the cast of 'Easy Rider' are to the US Marine corps.
Yes album covers
British artist Roger Dean created a series of dippy cosmic frescos that became famous by appearing on numerous album covers of glam prog noodlers, ‘Yes'.
Similarities: Besides the films of Roland Emmerich and the Lord of the Rings trilogy, there is no other film that looks more like it was based on a progressive rock concept album. Plus, it appears that the entire film takes place within the gatefold sleeve of Yes's 1974 folly, Tales From Topographic Oceans.
Differences: Very few. Although, Cameron's obviously filleted out the all the flying fish and Norse U-boats that were Dean staples.
Roland Emmerich's excruciating prehistoric parable pitted dreadlocked Mammoth-hunting dog-on-a-string types against cruel whip-wielding religious maniacs.
Similarities: Watch 10,000 BC, and see the obligatory sequence in which our heroes hunt down a toothy beast armed only with twigs and netting go straight from thrilling distraction to weary cliché. Cameron was clearly not paying attention...
Differences: It's not in space. It's in history.
Brimming with more fun than Stargate SG1 and fewer baffling political science lectures than Babylon 5, Farscape threw a US pilot into a civil war at the other end of the universe and left him to fend for himself.
Similarities: Agreeably meatheaded space-jock John Crichton finds himself dealing with a diverse mix of alien species and lost in deep space aboard a touchy-feely living spaceship with an ecological bent and a bunch of fuzzy freaks for a crew. Made in Australia.
Differences: It remains to be seen whether Avatar spends quite as much of its time with its lens trained on an endless parade of Aussie nymphets in fetish wear.
Lloyd-Webber's gaudy feline tourist trap based on TS Eliot's Old Possum’s Book of Practical Cats. The OST remains a big hit with widowers and Lexus drivers.
Similarities: Apart from the fact that the trailer comes across like an unofficial CG ‘Cats' sequel that's been filmed in the Rainforest Café, the blue-skinned protagonists look like they've been jetted straight from the West End stage and flung into the motion capture hangar.
Differences: Well, Jim Cameron has never really been one for modern dance freak-outs, but with this one, it looks like all bets are off.
Dances with Wolves
Kevin Costner goes native and turns on his former military comrades.
Similarities: It's an old, old story: boy meets tribe, tribe imparts ancient mystic wisdom, boy joins tribe, tribe kicks ass.
Differences: Sam Worthington is no Kevin Costner. But Kevin Costner was no Jim Cameron, so hopefully it evens out.
The Lawnmower Man
Untested CGI runs amok in the red-headed stepchild of the horticulturally-biased out-of-body sci-fi canon.
Similarities: Cutting (h)edge technology offers a differently abled, floppy-haired grease monkey (Jeff Fahey) the chance to kiss goodbye to his sit-down mower by gifting him powers and insights beyond human comprehension.
Differences: Fahey disappears into a version of cyberspace that looks to have been rendered on a hotwired Sega Megadrive rather than the skin of a ten-foot space monkey.
Avatar is released in cinemas on 17th December, 2009