Seagate Replica is an easy back up solution.

The so-called no touch disk drives designed to back up your computer's data and files are not new but one new device called Replica from Seagate, promises to do more with absolutely no touching needed.
The Replica is compact and nicely designed and comes in two sizes: a 250-gigabyte model selling for $130 and a 500- gigabyte version going for $2oo, both are compatible with Vista or Windows XP run machines.
Talking about PC with Windows XP operating system, it is noteworthy to mention that for some reason, the Seagate Replica back up device is not compatible with PCs equiped with a FAT32 -formatted C: drive.
Beside that little inconvenience, whichever version of the Replica you end up with, they both work seemingly and don't almost require any intervention ; just connect it to a PC or laptop via a USB cord and click twice to OK the initial installation and to agree to the terms of service. From there, the software loads onto your machine and begins backing up your entire entire hard drive to the Replica unit. If left plugged in, it will continuously back up all the changes made to your hard drive. Another nice thing about the Replica is that it comes with a recovery disc that allow you to boot up a crashed PC or laptop in no time.
The reviews for the Replica are generally good and put it right in the company of other external back up device like the Clickfree HD325 whch sells for $180 for 320GB hard drive.

For more, see pcmag.com