Look at the sci-fi films of years gone by, and among all the shiny rocketships and teleporters, there's one thing that they didn't predict: streaming movies at the touch of a button.
Fortunately, we live in Space Year 2015, where we have such things as the internet; no longer are we bound by the tyranny of the DVD shelf. But with so many films available, how do you whittle them down? We've picked out the best sci-fi on the web, from mind-bending time travel flicks to big-budget action.
In the brave new world of genetic engineering, getting a seat at the top table takes more than good breeding - you need a perfect genome. Ethan Hawke stars as an "Invalid" whose dreams of space travel are thwarted by his DNA - so he borrows Jude Law's superior genetic stock to swindle his way on to the space program. When the program director's murdered, though, he finds himself in the frame.
For all that it bills itself as a chilly, utopian vision of the future in the mould of THX-1138 or Things To Come, Gattaca is actually more of a potboiler; a swindler is on the verge of being found out, becoming progressively more twitchy and paranoid as the cops close in. But its sci-fi trappings are thoughtfully observed, conjuring up a two-tier society that's alarmingly plausible.
Cowboys & Aliens
This adventure film commits wholeheartedly to its outlandish premise, treating it with far more seriousness than it deserves: there are cowboys, and there are aliens. Deal with it.
Winks to the camera are kept to a minimum; when alien invaders attack a frontier settlement with vastly superior weapons, there's a very real sense of threat. Harrison Ford turns in his most heartfelt performance in years as acerbic Colonel Dolarhyde, while a steely-eyed Daniel Craig riffs on Clint Eastwood as a Man with No Name – and no past.
Like Super 8 – also released in 2011 and produced by Steven Spielberg – it's an homage to Spielberg's early work. Where Super 8 paid tribute to the family dynamic of Jaws and Close Encounters, Cowboys & Aliens director Jon Favreau riffs on the rip-roaring adventure of Raiders Of The Lost Ark. The early scenes building up to the eventual reveal of the aliens, are a highlight – recalling the menace of Jaws.
Rather unfairly overlooked on its release, Cowboys & Aliens is overdue for a reappraisal.
Star Trek: First Contact
When the Borg attempt to travel back in time to prevent mankind making first contact with the Vulcans, it's down to Captain Picard and the crew of the Enterpirse to thwart them. Star Trek creator Gene Roddenberry envisaged a utopian future free of conflict; First Contact chucks such lofty aspirations out of the airlock, gleefully pitting the phaser-toting Enterprise crew against remorseless cyborg adversaries in what amounts to a restaging of Die Hard aboard a spaceship.
It's smart in borrowing from the series' best entries; Picard's obsessive pursuit of the Borg echoes the Moby-Dick allusions from The Wrath Of Khan, while a fish-out-of-water time-travel comedy subplot is taken straight from The Voyage Home.
The War of the Worlds
No, not the Tom Cruise version – though that's also available online. This is the 1950s film, which relocates the action of HG Wells' novel from Victorian England to Southern California. The effects have dated a little – tellingly, it makes no attempt to recreate Wells' alien tripods, with the Martians instead jetting about in what look like oversized desk lamps.
Despite that, there's a visceral quality to the action, as the armies of the world are beaten back by the invaders; not surprising, considering that the Second World War was still fresh in the minds of the film-makers and the audience.
Even the departures from the novel make sense; in the atomic age, the USA occupied the dominating position that Britain had when Wells' novel was published, so shifting to a contemporary American setting recreates the impact that the novel had on audiences reading it for the first time.
Joss Whedon's sequel to his short-lived sci-fi series Firefly had a thankless task; winning over new viewers while keeping the fans happy – and wrapping up seven seasons' worth of plotlines in two hours. And Whedon pulls it off, pretty much: Serenity appeals to newbies almost as much as seasoned Firefly veterans.
Its scuzzy, lived-in sci-fi world where good and bad is far from cut-and-dried is more believable and more appealing than the clean, black-and-white settings more common to space operas, there’s action aplenty, and its cast of flawed characters makes for an enjoyable emotional ride. But it couldn’t serve to satiate Firefly fans, of course, leading to frequent calls for the series to be brought back, Arrested Development-style, for a true final season.