The latest company to jump into the removable disk market is Seagate - and rather curiously, it seems to think it's the first to do it, even though its FreeAgent Go uses the exact same scheme as Quantum and ProStor (and therefore also Tandberg Data, Imation and Dell).

That means it's putting a standard 2.5 inch SATA hard drive - made by Seagate, naturally - into a shock-protected case. The drive module then slots into a docking station which is connected to a PC or Mac.

And that's pretty much it. Sure, it comes with software to do scheduled back-ups, 256-bit AES encryption and multi-computer synchronisation, and it is available in four different colours (unless you're a Mac user, in which case you've a choice of silver or silver. The Mac version does have a Firewire port as well as USB though, where the PC model is USB-only).

It's also cheaper than the likes of RDX - £150 will get you a 500GB drive module; the dock and its carrying case add another £20 or so.

But the main thing is it saves you having to mess about with plugging in a cable. So how does that make it "the first external hard drive to offer a docking option", as Seagate claims?

Jean-Frederic Bistagne, the company's "senior director for branded solutions EMEA" gamely countered that it's a first for "our target market - consumers and micro-businesses" (the latter's a term I'd not heard before, but it could yet prove useful!).

"This is not [built to] the same industrial shock and vibration requirements," he said, adding: "It is consumer-grade and not aimed at the tape market. The main difference comes from the software."

That this makes it a first may come as a surprise to the likes of Tandberg Data, which had already realised that removable disks aren't substitutes for tape.

Still, the fact that the 800lb gorilla of disk drives has recognised the potential of removable hard disks should give confidence to anyone thinking of buying this type of technology. And if it's for business use, at least you know now that there are both consumer and business-grade types available.

I'm a little perplexed though: I can see the attraction of cableless docking stations for gadgets such as iPods or mobile phones, where you want to synch the device but also need to use it on the move. But external hard disks - surely they're only going to be used at a desk?

A question then: If you use an external hard disk, how often do you move it between PCs, and is it often enough to make it a nuisance to have to plug in a USB cable each time?