Hitachi senior vice-president Bill Healy says that if current trends continue, by 2025 a standard 3.5in hard drive could contain up to 20TB (terabytes) of your data. Well that's if any manufacturer will still bother to make models in this format.

Driving the immediate surge of capacity is PMR (perpendicular magnetic recording). This overcomes the limitations of traditional longitudinal magnetic recording and packs much more data into a far smaller physical area. The first hard drives using PMR reached the market in 2005. Seagate's chief technology officer, Mark Kryder, tells us that the company's forthcoming hard drives will all be PMR drives.

HAMR (heat-assisted magnetic recording), in which platters are made from materials that can support a denser number of bits, should be with us in about five years' time. Patterned media, which forgoes a uniform layer in favour of 'islands' of material that do not physically touch, is on the horizon, but further off. Optical's future is less certain. The battle between Blu-ray Disc and HD-DVD, two competing but incompatible blue-laser formats, has no clear winner in sight. Gartner's Steve Kleynhans says: "As long as there are two solutions battling it out, there will never be a critical mass established, which will keep prices high."

Meanwhile, one potential exciting upgrade to flash media could come in the form of ultradense probe storage, which is being developed by Seagate, among others. It's based on technology borrowed from electron microscopes and could cram 10GB into a device the size of an SD Card.

Read more: the future of technology revealed