In 2007, Data Robotics, Inc. came out with a new desktop storage product called the Drobo which could be attached to your desktop or laptop using a direct USB or Firewire connection. The Drobo provides redundant data protection through their leading edge technology named BeyondRaid™ and originally supported up to 4 hard disks. The Drobo brings advanced RAID capabilities to home users with little technological knowledge and very little configuration required.
An additional device called a DroboShare could be purchased to act as the computer and when attached to your Drobo the pair of devices would simulate a NAS.
In early 2010, the much awaited Drobo FS was released and is a true NAS version of the Drobo. The Drobo FS supports the same BeyondRAID™ technology and up to 5 hard disks.
See the Drobo Website for additional details.