Best NAS drive: 8 on test

NAS (network attached storage) devices certainly aren't the most glamorous gadgets you can have in your home. A network-connected hard drive might seem like a remnant from a home office – a backup necessity for over-paranoid users and not much more.Early NAS devices – and even some new no-frills budget ones – do little more than allow any computer that's connected to a network to access an external hard drive as if it was physically installed in the computer. However, a lot of new NAS devices have some great features built in, which can completely transform what your home network is capable of. Not only can they act as media servers throughout your house – letting your devices access and stream music and videos to any device on the network – they can also be used be used to stream your media across the internet, letting you access the files from anywhere in the world, and effectively allowing you to create your own version of Spotify or Netflix.As for cloud backup and synchronisation services, while you could pay Dropbox the equivalent of $9.99 a month for 50GB of space, with a NAS device you could have your own service with huge amounts of storage (some NAS devices accept hard drives of up to 3TB) without monthly fees or the need to trust your private data to a third party. We've gathered the best NAS devices on the market to find out just what they are capable of.