Jetpacks. Flying cars. Hotels on the moon. Dinner in pill form. The reality of life in the early 21st Century is crushingly different to the optimistic predictions of the 1950s.
But the idea of mind-blowing hyper-fast travel is something that could actually happen.
Possibly.
SpaceX and Tesla founder Elon Musk has unveiled the initial designs for his proposed "Hyperloop" system. Musk, who also co-founded PayPal and was the inspiration for Robert Downey Jr's portrayal of Tony Stark in Iron Man, teased the announcement on Twitter back in July.
And now it's here.
So what is the Hyperloop? Will it literally ever get off the ground (or under it)? And what other 'rival' innovative train-like projects are out there?
Most importantly, if the Hyperloop ever makes it past the design or prototype stage, what are the implications for us? How would it change the world?
Next level transport
The Hyperloop has been hyped up as a game-changer. A paradigm-shifter. In theory it could transport passengers from Los Angeles to San Francisco in 30 minutes, and has been described by Musk as "a cross between a Concorde, a railgun and an air hockey table".
The technology has been billed as safer, faster, cheaper and more sustainable than existing methods of travel. Musk also claims the Hyperloop would also be 'immune' to weather. And never crash. It could even become the fifth form of transport (after automobiles, planes, boats and normal trains).
Which sounds pretty awesome. But how would it actually work?
Musk has revealed a vision of futuristic networks transporting floating capsules using magnets.
Basically, it's a pod in a tube.
The Hyperloop would be powered by a combination of batteries and electric induction motors along the tube - all of which would run on solar power.
The idea behind the aerodynamics is to use a compressor on the front of the pods, which will create a smooth air cushion the pod can ride. Musk estimates the pod capsules would travel somewhere in the region of 1,200 km per hour.
The Hyperloop would cost approximately £5 billion to build, and according to the tech maverick it will be the next best thing to teleportation.
Real world application
So what impact would a real Hyperloop have, once it's finally built? Well, if modern air travel and the web have made the world a global village, the Hyperloop could turn the us all into neighbours.
Time saved travelling could make daily commuting to another country - or continent - completely feasible. It could make long-distance emmigration, travelling and holidaying more attractive, and make short term trips to see friends and family in distant corners of the globe a real possibility.
The environment would be a winner, too. Mass 'Hyperlooping' would mean a reduction of air traffic and carbon emissions. It would mean a less oil dependence and greater utilisation of renewable energy.
And that's not all.
As the cleanest form of transport, well, ever, the Hyperloop would seriously cut noise pollution, air pollution and general road congestion - meaning fewer road accidents and a safer world for drivers and passengers.
Musk has suggested the system would work best connecting cities less than 1,000 miles apart, but could the technology one day stretch to connect the entire globe?
Imagine a trip from Manchester to Melbourne, or Berlin to Beijing, only taking a few hours.
Some potential drawbacks
The economic picture is less clear. While estimates suggest Hyperloop could become a lucrative cash cow for investors (with a projected £58 billion return over 30 years), would it generate a net increase in jobs, or would a decline in air travel mean a net loss of jobs?
And what of the cultural impact - could ultra-fast transport create the same expectation of a prompt face-to-face response the way email, IM and social media have created pressure to respond immediately online?
Then there's leisure travelling. Would the time-saving technology lessen the romance of exotic 'long-haul' destinations? Could we get complacent about appreciating different cultures when distant locations become as accessible as driving to a neighbouring town?
There's no stopping technology, of course. Once something has been invented, you can't un-invent it. As always, we'll need to embrace the advantages and manage the potential downsides.
If the Hyperloop does ever go ahead as a full-scale project, it will be without Musk himself. He's already revealed he's way too busy with his existing projects to dedicate himself to another tech venture that could change the world. Which is fair enough. Musk will work on the subscale demonstrator, but will make the alpha designs open source - meaning anyone can amend or build the Hyperloop.
But even if the Hyperloop is technologically viable, any number of factors could mean it doesn't become a reality; bureaucracy, insufficient financial resource or a lack of political will could all put the brakes on.
The Hyperloop 'competitors'
If the Hyperloop stumbles, there are plenty of ambitious concepts ready to take up the challenge. The ET3 consortium plans to take travellers from New York to London in an hour by putting a superconducting magnetic levitating train into an evacuated tube and firing it towards its destination at about 6,500 km per hour.
Elsewhere, Terraspan wants to construct a vast underground superconducting energy grid, which vacuum trains could use to zip passengers between distant locations in a brain-meltingly short time.
Swiss company Acabion, meanwhile, is aiming to develop "streamliners" - vacuum tube-capable vehicles that could one day replace cars. The proposed design of the streamliners is a sort of fighter jet cockpit on wheels to transport passengers around the "traffic internet" at unimaginable speeds.
Finally, the Startram orbital launch system could see public transport magnetically levitated into low Earth orbit via an evacuated launch tube. Yes, really.
For the time being we'll be searching for traditional wheels-and-track trains on sites like Direct Rail. But who knows where the future of 'train' transport will take us? Maybe it'll be subterranean. Maybe it'll be the street or the skies.
Or maybe it'll be the stars.