Western Digital today added a new member to its My Book line of external hard drives. The My Book Mirror Edition is a USB-only, dual-drive unit with RAID 1 redundancy. The 1TB model costs $290, and the 2TB model costs $550. With your data mirrored on both drives, your total storage space is half the stated capacity. The My Book Mirror can be configured with RAID 0, should you want to make use of the full capacity of each drive.
The My Book Mirror's two hard drives are replaceable--no tools required. The drives feature Western Digital's GreenPower technology, which, according to the company, helps the My Book Mirror consume 33 percent less power than other dual-drive enclosures. Another bonus: these energy efficient drives don't require cooling fans, meaning the My Book Mirror should make for quiet desktop companion.
Should you have multiple PCs in need of redundant backup, it should be noted that WD's My Book World Edition II is a dual-drive NAS drive that adds only $50 to the price of the My Book Mirror--$600 for the 2TB model.