What do you do if you need ultra-high storage capacity and the likes of Blu-ray and HD-DVD won't cut it.

You could opt for holographic-based storage. That's what a number of government agencies and education resources are currently evaluation as a means of safeguarding their voluminous data stores.

InPhase Technologies is a leading proponent of holographic storage, and it had a writer on display, along with a 300GB disc from Maxell.

Holographic storage works by splitting a single laser beam into two separate beams, that is, a data-carrying beam and reference beam. The intersection of the two beams is where the data on the disc is recorded. By varying the angle of the reference beam it is possible to have more than one set of data in the same location, meaning higher densities and capacities than traditionally available.

Reading of the recorded data is undertaken by shining the reference beam at the correct angle, allowing for the stored holographic data to be read. Filters are used to ensure that overlapping data, which coexists in the same place, isn't read by mistake.

Maxell and InPhase reckons that the holographic discs, encased in a cartridge for protection, will hit 1.6TB capacities and 980Mbps read speeds by 2011.

The technology is currently far too expensive to appeal to the average home user, but it has significant potential nonetheless.