Rich Ericson

Maxtor Corp.'s Central Axis ($319.99) offers a new way to add a centralized, always-available terabyte of storage to your local network, whether you install it at home to share media files or set it up at work to share proposals among your colleagues. You can even stream your media to UPnP AV-compatible (Universal Plug and Play Audio/Visual) networked entertainment systems without using a computer. Best of all, by setting up an account with Seagate Global Access, you can store and retrieve files from the Central Axis device over the Internet.

I tested the drive with Windows XP and Vista desktop and laptops. The SATA II, 1TB drive is compatible with Mac OS X 10.4.11 or later. You'll also need IE 6 or later, Firefox 2 or later, or Safari 3.1 or later to handle administrative tasks.

USB 2.0 is the most popular connection technology for external devices, with FireWire (either 400 or 800) a close second. However, if you really want extreme speed, eSATA is the way to go, as Seagate Technologies' new FreeAgent XTreme drive proves.

I tested the 640GB model (ST306404FPA2E3-RK, $179.99). The drive includes the unit itself, a one-piece power supply, a quick start guide (basically an illustrated "what to plug in where" sheet), plus one USB 2.0 and one Firewire 400 cable. No eSATA cable is provided. Installation is simple: plug it in, connect the appropriate cable, turn on the drive, and you're ready to go.

To be truly effective, a backup application must let you easily choose what you back up, simplify recovery and not slow down your work. So I was looking forward to evaluating DataSentinel, a combination of hardware, software and storage service.

The hardware -- a 512MB thumb drive -- comes preloaded with the backup software. The software loads automatically (and prompts you for a password) when you insert the thumb drive in any USB slot. The files you select are stored on DataSentinel's servers, for which you pay a fee, beginning at $5 a month for the first 5GB.

There's no such thing as too much protection for your valuable files. Although external hard drives can provide backup copies of files on your hard drive, what if you use external drives for primary storage? Sure, you can use yet another external backup drive, but a better solution might be a RAID array with two drives. Western Digital offers such a system with its new My Book Mirror Edition ($549.99).

Packed inside a 6.5-by-6.1-by-3.9-in. black enclosure are two hard drives that connect to your system via a single USB 2.0 port. The My Book is preconfigured as a single Windows NTFS partition using RAID 1 (mirrored) mode for a total capacity of 1TB. Files saved to this "primary" partition are automatically copied to the "secondary" drive, which is hidden from view. In fact, files on the second drive can't be directly viewed by, say, a file manager, and cannot be accessed from applications). An additional note: Mac users must reformat the NTFS drive to HFS+ (Journaled) or FAT32 formats.