If a significant portion of your income is made by working on a computer, you should consider installing a redundant hard drive in your computer and making a RAID array. This will ensure that if one drive fails, the other can take over. And you can continue working during a disk failure, the most common hardware failure.
It's a new world for geeks like us. It used to be that business owners would throw up their hands and shriek, "Get me Blue Circle!!" whenever faced with a technological challenge.
It used to be that there was a business side and a IT side, and neither had any interest in the other. Now, they are absolutely linked, and it is professional suicide to think that one could exist without the other. Talk about your paradigm shift.
If you are an individual or small business, you should strongly consider an online backup service like Carbonite or LiveVault. Why?