I've been a fan of drive imaging for a while now. I used Norton Ghost in my first job after college to clone drives for testing in the lab and a couple years later I bought Acronis True Image for backing up my home computer. Imaging an entire drive instead of just backing up documents, pictures, music, etc. not only conserves your irreplacable data, but it also provides an easy path to rebuilding your entire system.
As many of you will notice, Ghost and True Image are Windows programs, although Acronis does have a True Image Server product for Linux. There are some quality imaging apps for non-Windows environments as well. I say non-Windows because g4u (Ghost for Unix), doesn't run on Linux, but uses NetBSD instead. Despite this fact, I added it to the Linux App Finder database for the same reason I add web apps, g4u can be still be used if you run a GNU/Linux OS. This is possible because g4u is not just a simple program. It is released as a boot disk which makes it useable for any operating system with supported file systems.