If there ever was a software application that deserved a WOW, that is Acronis's True Image. I mean WOW! Seriously. I have never seen such a powerful, intuitive and beautifully designed back-up software as True Image. It lets you backup your entire disk, including operating system, etc. Not only that, it has an amazing compression ratio. It lets you explore images, restore. And here's the best part: you can do incremental backups of existing images. When you first install it, it prompts to create a boot up disk so that in case your system fails you can restore any image easily. Wow! I am VERY impressed. Well done!
And if all that wasn't enough, it costs less than 40 Euros!