We asked two of the world's top tech thinkers to cast judgement on concepts seen in some well-known films.

From memory implants in Johnny Mnemonic to the paranoid ship's computer in 2001, from uploading a virus to aliens in Independence Day to universal translators in Star Trek, we asked for advice from Peter Cochrane, entrepreneur and former CTO at BT, and Ray Kurzweil, inventor and futurologist.

Here they explore the credibility of some of the enduring scenes Hollywood has churned out. How credible are the ideas on show, when might they become reality (if at all), and what do we make do with for now? Read on, and feel free to add a Reader Comment of your own...

JOHNNY MNEMONIC
Film: Johnny (Keanu Reeves) couriers information by uploading data to his brain from a computer, only for it to be downloaded at a later time in another location.
Concept: Using the brain for information originally stored elsewhere, possibly encrypted, or indeed upgrading human memory using plug-in chips, PC-style.
Now we have: Fundamental electronic connectivity I/O for motor applications, the first brain activity scanners. Neural implants for deafness (i.e. cochlear implants), Parkinson's disease, and other impairments. Also a rudimentary idea of how the human brain works and is organised, but no way of extracting or injecting information.

PETER COCHRANE: People have been using their brains as bit transport for millennia - we hear, see, feel, smell, and convey to others via language and pictures. I think the real contest is with electronics which look set to exceed our mental and storage capacities within the next 50 years. Chip implants for hearing are now common, chips for motor and sight restoration are at an experimental stage and it is only a matter of time before we move onto memory augmentation. But today our technology looks like smoke signals trying to communicate with a mobile phone.
Credibility rating: 3/10
How many year's time?: 40

RAY KURZWEIL: Downloading and/or uploading information to/from the brain will require substantial integration of biological and non-biological intelligence. We've started down this road with contemporary neural implants. Ubiquitous and non-invasive brain implants using 'nanobots' (robots the size of blood cells that will travel through the capillaries of our brains and communicate with our biological neurons) will start around 2030, and will be deeply integrated with our thinking process in the 2040s.
Credibility rating: 10/10
How many year's time?: 40 to 50

2001
Film sequence: Paranoid spacecraft computer HAL2000 'reasons' with stranded astronaut Dave Bowman (Keir Dullea) about why he locked him out of the ship.
Concept: The idea of a computer becoming so complex it can understand, reason, listen, speak and interact in the same way as a human, including using deception and self-deception.
Now we have: Machines that learn, software that breeds/replicates. 'Narrow AI,' i.e. computers that can perform 'narrow' tasks that previously could only be accomplished by human intelligence, such as playing games (e.g. chess) at master levels, diagnosing electrocardiograms and blood cell images, making financial investment decisions, landing jet planes, guiding cruise missiles, solving mathematical problems and so on. Currently exponential progress curve showing no sign of slowing down.

PETER COCHRANE: The principal reason our machines are failing to develop true intelligence is that they are deprived of all sensory input. Today we cannot define, describe, quantify or measure life, intelligence or emotion. Until we can, discussion is mostly a waste of time. We may not be smart enough to get there without machine help - but they may become smart enough to do it without ours!
Credibility rating: 9/10
How many year's time?: 20

RAY KURZWEIL: Although HAL was paranoid (a not uncommon human condition), he operated at fully human levels of intelligence. He could pass a Turing Test which requires being able to respond to dialogues in a way that is indistinguishable from humans. I expect that machines will pass the Turing Test by 2029.
Credibility rating: 10/10
How many year's time?: 30

INDEPENDENCE DAY
Film sequence: Captain Steven Hiller (Will Smith) and brilliant MIT graduate David Levinson (Jeff Goldblum) save themselves and the rest of humanity from the scourge of unpleasant and territorially acquisitive aliens by uploading a computer virus from their Apple PowerBook to the mother ship, fatally crippling the invading fleet. (Ed. Anyone remember how they did the uploading? Wireless LAN? USB - universal serial bus, geddit? Written in Java??)
Concept: The idea of using malicious code or malware as a positive weapon to disable enemy machines during a military campaign.
Now we have: Information warfare - a major military tactic. The US military already uses electronic devices to jam enemy communications and is investigating the use of software viruses and other information pathogens.

PETER COCHRANE: This is the here and now - it works! And it comes in numerous sophisticated forms e.g. 1) Wipe the memory clean now or at some pre-defined trigger point, 2) Corrupt memory so that errors are imperceptible to the user but significant for you, 3) Change the software to do your bidding now or at some later date.
Credibility rating: 10/10
How many year's time?: 0

RAY KURZWEIL: Information warfare will grow in its importance. I put 40 years because we are not yet in a position to completely disable an enemy through software pathogens (e.g. viruses). This would require our enemies to be largely dependent on software-based intelligence. However, prior to these scenarios, we will be greatly concerned with biological terrorism and warfare, and in particular with biological pathogens that are genetically altered. This involves the combination of information technology and biological knowledge.
Credibility rating: 10/10
How many year's time?: 40

STAR TREK
Film sequence: A universal language translator on starship bridge/uniforms enables Captain James T Kirk (William Shatner) or Jean-Luc Picard (Patrick Stewart) to conduct negotiations with alien life forms.
Concept: The idea of software which can easily and accurately translate language, including nuance and expression.
Now we have: Software that can automatically translate documents from one language to another e.g. AltaVista's Babel Fish, named after the fish in Hitchhiker's Guide to the Galaxy that fed off brain waves and could translate any language in the universe. Although this type of software makes mistakes, the quality is often better than people expect.

PETER COCHRANE: This works right now at a very basic level for text and speech - but not at the level of natural language spoken interchange. Computer speech recognisers are better than humans today on a word-by-word basis, but they lack cognition and contextualisation. Until machines become fully sentient we will not be able to realise the Babel Fish. Look at the trouble human translators have. Ultimately I think machines will be better but will fall short of the ideal Babel Fish.
Credibility rating: 7/10
How many year's time?: 0-25

RAY KURZWEIL: We have speech recognition, language translation, and synthetic speech today. The quality is far from perfect, but getting better every year. The quality demonstrated in these movies requires human level intelligence, which I expect by the year 2029.
Credibility rating: 10/10
How many year's time?: 30

BLADERUNNER
Film sequence: Opening sequence where bladerunner Holden (Morgan Paull) tries to identify replicant Leon (Brion James) as an android by testing his emotional response to questions. Roy (Rutger Hauer) later demonstrates emotions in his desire for life.
Concept: The ability for artificially intelligent devices to feel emotions.The idea of software which can easily and accurately translate language, including nuance and expression.
Now we have: Current research at MIT, Carnegie Mellon University and elsewhere to develop software programs and robots that have emotional awareness and can provide appropriate responses to emotional cues e.g. the robot Kismet, developed by Cynthia Breazeal at MIT Media Lab, which can recognise the emotional state of a person through their speech patterns and then responds with an appropriate 'emotional' facial expression.

PETER COCHRANE: This is only likely to be a matter of time. My guess is that once a machine is truly sentient, connected to our world through adequate sensors, with fully adaptive hardware and software, with an evolutionary (replication/reproductive) capacity, it will follow naturally. All animals show emotion of varying degrees and we can expect machines to follow. There appears to be nothing special about carbon life - it is just that we have never seen any other forms.
Credibility rating: 9/10
How many year's time?: 50

RAY KURZWEIL: Our ability to recognise and respond appropriately to emotion is part of our intelligence. Indeed, it is the most complex and most intelligent thing that we do. Mastering emotion by machines will require machines with human-level intelligence, which will occur by 2029.
Credibility rating: 10/10
How many year's time?: 30

Peter Cochrane is the co-founder of ConceptLabs and spends his time around the world getting innovative start-ups off the ground and evangelising technology, among other things. He is well known as the former head of BT Labs, Martlesham, when he was CTO at the telco, and is a writer on various technology issues.

Ray Kurzweil is the founder, chairman and CEO of Kurzweil Technologies, known for a print-to-speech reading machine for the blind as much for his piano synthesiser and other breakthroughs. He wrote The Age of Intelligent Machines while at MIT and was awarded the 1999 National Medal of Technology by Bill Clinton.