A terabyte is a 1000 gigabytes and can be yours for less than $250. That's amazing! Storage prices have come down so much in the past couple years, you really do not have an excuse to be backing up data. About a year or two ago, hard drives were about $1 per gigabyte and you needed multiple drives to reach a capacity of 1 terabyte. Now you can get a single external terabyte drive for less than 25 cents a gigabyte.
I have recently purchased a Maxtor OneTouch 4 Plus and a LaCie Big Disk Extreme +. Both are external drives and support USB 2.0 and Firewire 400 connections. The LaCie also supports Firewire 800. If you are on a Mac, use Firewire. It offers you a faster sustained data transfer that is less CPU intensive than USB.
You can daisy chain the drives together or attach a camcorder to the drive to import video. LaCie even offers a mini rack to stack multiple drives. Why would you want multiple terabyte drives? If you do a lot of video or photography, you need a lot of space. I upgraded from a 320 GB Maxtor to the 1 TB Lacie for backing up my MacBook via Time Machine and to have more room to work on video files since I only have about 12 GB of free space on my internal 160 GB drive to spare.
The LaCie drives comes pre-formatted for Macs with HFS+. The Lacie is a very solid and heavy drive. I do not think it would be very suitable for traveling. It has a auto power feature to be more energy efficient. It makes a little more noise when it is running than the 320 GB Maxtor that it replaced, but not much more and only when it is spinning up. The Maxtor 1 TB comes formatted for Windows computers.
However, if you have some extra money the ideal solution is the Drobo. It is a small black box that holds four SATA 3.5 inch hard drives of any size and manufacturer. It offers redundant and almost infinite storage better than RAID 5, because it does allow you to mix and match drives of different sizes. It also easily rebuilds failed or replaced drives. For example, you can start out with a 160 GB, 2 250 GB drives and a 320 GB hard drive. When the 160 GB drive gets full the Drobo will let you know and you can swap it out and replace with a larger drive. You do not need to shut down the device, disconnect it or anything else. Drobo keeps on running and serving data. No additional software or drivers are necessary. The few downsides are that it is expensive at $450 for an empty enclosure. It only supports USB 2.0 and the network interface is sold separately for another $200.
