Everyone knows the price per gigabyte of storage on normal computer hard drives has been tumbling for years, so where next for manufacturers hoping to maintain their bottom lines? Apart from physically smaller disks and solid-state drives, one growth area is RAID drive arrays, such as the 4-terabyte monster from Buffalo Japan .

RAID is essentially a technology that can keep multiple copies of data on physically separate disks within a single enclosure - it stands for 'redundant array of inexpensive (or independent) drives' and comes in several different configurations.

Faster transfers

Buffalo's 4TB TeraStation TS-2UH4.0TGL/R5 costs ¥360,000 (£1,500), contains four separate drives and can be set up as any of RAID 0, 1, 5 or 10 to provide a spectrum between maximum storage and maximum backup security. (Check out Wikipedia here for more details on RAID if you're interested.)

There are two USB 2.0 ports for connecting additional external drives and a gigabit Ethernet connection that allows data transfer at up to 38MB/s. Automatic backup software (Windows only) is included and UPS support means power cuts won't physically damage the disks.

With products like the TeraStation range already displayed prominently on the shelves of consumer outlets in Japan, it's certain that such large storage arrays will become commonplace in the home before long.