You could be forgiven for mistaking the LaCie FastKey for a standard USB flash drive. However, the FastKey is a bit special, bridging the gap between traditional USB drives and external hard drives.

The small size makes it incredibly portable, although with 120GB of your precious data stored on it, you won't want to take it out and about too often. Handily, it can sit unobtrusively in a PC or connected to a router to create a NAS device.

The reason it's so small is because it's a solid state drive, and the lack of moving parts means it's also very fast. In our tests, it took just 16 seconds to transfer a 1GB file, with the average speed being 93Mb/s.

The FastKey comes in three sizes, 30GB, 60GB and 120GB, with performance increasing according to capacity. We tested the 120GB version, which performed very well, but it's disappointing that opting for less storage space means accepting a drop in speed.

Even so, the LaCie FastKey does a good job of backing up important files. Although it doesn't come with back-up software (which Seagate is keen on providing with its external hard drives – often to the annoyance of its customers due to the quality of said software), the FastKey includes powerful AES 256 encryption and a two-year subscription for 4GB of online storage.

The build quality is great too, with an outer shell made from aluminium, but there's no escaping that this is an incredibly expensive external hard drive – especially in its 120GB incarnation. There are plenty of alternatives that will do just as much for less.

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