Holographic storage reared its head again this week. Saluting decades of research, US giant General Electric talked up its micro-holographic discs -- a revolutionary way to store vast amounts of digital information.
But holographic storage is just one of many ultra high-capacity storage media touted for future use by consumers. From multi-terabyte media as small as a fingernail, to formats relying on light-activated biological proteins, we're going to explore five of the most interesting technological promises.
Proteins are delightfully complex little molecules, linking up amino acids to their hearts' content, day in, day out. Go ahead, look in your diet -- you'll find some. Look into the future, and you might find your DVDs are coated in a layer of genetically modified light-activated proteins, capable of storing tens of terabytes of data.
It'll be the result of research by one Professor Venkatesan Renugopalakrishnan of Harvard Medical School in the US. He and his colleagues have modified the DNA of a protein called bacteriorhodopsin which, when exposed to light, naturally changes its molecular state for a few hours, before returning to normal.
Renugopalakrishnan ('Prof' to his mates, we imagine) thought these two possible states could represent digital information, which is also stored in two states -- zero and one.
By engineering the proteins to remain in an altered state for several years, he thinks discs packed with them can be used to store digital data. And enough proteins can fit on the face of a standard-size DVD that up to 50TB of information could be contained at any one time.
A prototype was built in Japan in 2006, but mainstream commercial use is still a long way off.
Rainbow technology is a curious one, juxtaposing the old with the new: paper and digital data. It's a system that uses normal paper to store huge amounts of data.
An Indian scientist called Sainul Abideen from the MES College of Engineering, Kerala, developed the technology, which uses various tiny coloured shapes -- printed on plastic or paper -- to store data. And he has claimed his Rainbow technology will be able to store 2.7GB of data on a 25mm-square piece of paper.
And he's demonstrated a working system. He compressed a 45-second audio clip on to a plain sheet of A4 paper. And 450 pages of plain text (roughly 1.47MB of data) was stored on to a 25mm square of the same material. Hardly 2.7GB, but it's a start.
In our previous coverage of Mr Abideen's work, we quickly pointed out some of the obvious problems: paper is easily damaged and decays over time, and whatever algorithmic compression technique he has developed for use within this technology would have to be far more impressive than this Rainbow printer itself.
It'll come as no surprise that you can't buy a Rainbow printer yet. And we're not holding our breath. But it's a nice idea.
A company called Colossal Storage (excellent name) in the US is developing a removable computer disk with the potential, Colossal CEO Michael Thomas claims, to store between 10TB and 10PB (petabytes) of data, or even more.
These theoretical disk drives would sit in the same footprint as today's desktop hard disks. But instead of using magnetic platters as existing disks do, Colossal's disks would use 'atomic holographic optical nanotechnology', a type of holographic storage.
Simply put, it uses ultraviolet lasers to read data stored in three dimensions, instead of the two we use on discs today.
Less simply, but more interestingly put, it uses ultraviolet light to write data, by modifying the position of a molecule to represent either a 1 or 0 binary digit within one of Colossal's FEdisks (known as 'Transparent Optical Media'). This can then be read as data with an ultraviolet laser.
And what's more, that data will remain intact for over a century, Thomas claims.
This has yet to even hit the laboratory stage, and is unlikely to until at least next year, though ComputerWorld reports production could start as soon as 2012.
SDXC is the future of SD card technology, with a theoretical maximum capacity of 2TB -- that's 2,048 gigabytes.
At the moment, SDHC cards commercially max out at 32GB. It suffices, but it soon won't. Already camcorders are shooting in 1080p, and it won't be too long before they shoot in 1080p that doesn't look like a haggard mess of modest bit-rate artefacts. Phones, too, are beginning to support not only HD video playback, but capture too.
The technology will be available in smaller SD card formats as well, such as microSD and Sony's Memory Stick Micro M2 cards.
It'll be several years before you'll see microSD cards in the terabytes. But a time will come where a 512GB microSD card will seem like a bitter memory of the past, inadequate for all but the most paltry of storage requirements.
And now, some present-day holographic storage news, and the catalyst for our look to the future of ultra high-capacity data storage. General Electric this week unveiled a micro-holographic disc with the capability to store 500GB of data. Aimed at archivists, but ultimately at us lowly consumers.
They're the same size as today's DVDs, and similar to the holographic storage media we've already discussed, store data in three dimensions rather than as pits in a disc.
We expect this will be a pre-recorded medium to begin with, loaded with the next generation of video formats. Darren Waters on the BBC News technology blog wonders, "A single GE disc could be used to package up a library of high-definition movies, but is there pent-up consumer demand for such an offering?"
We can't help think Mr Waters may have missed one crucial point: such a pre-recorded disc could be used to store tomorrow's video content: 3D TV, or images with much higher resolutions than Blu-ray's 1080p. It's not going to be used to peddle our measly current-generation videos. The very thought!
Which of the media we've looked at today do you think hold the most promise? Will there even be a point, when the future seems to be ploughing head-first into cloud computing and remote storage? Let us know in the comments below.