This 34mm ExpressCard slots into an available slot on your laptop and adds 4GB of storage space. As the card hides completely away, it can be installed and left as a backup for your files. To make this easier, Lexar has installed No TouchBackup, which can automatically back up your system to a schedule that suits you - even daily if needs be.

When it comes to transferring data, it's not as quick as having an external mechanical hard drive installed as Flash can't write as quickly. We managed to copy 1GB of files in 2 minutes and 15 seconds, which is relatively slow.

The capacity of the card is good value for money and the everyday functions it offers makes this a great back-up tool for the frequent traveller. As capacities grow and the cost of such cards drops, such devices will become as important to mobile users as their USB memory keys.