Buffalo's LinkStation Pro Duo NAS device houses two drives for up to 4TB of storage. It can be set to run in RAID 0 or 1 modes and, coupled with its Gigabit Ethernet interface, this means it will be quick to perform network file transfers. It has a good array of features, including lots of server functions and a built-in BitTorrent client. Home users and small business users alike should get plenty of use out of this NAS device.