What’s the most important component of your computer? The cpu? That expensive graphics card? The three monitors that you’ve plugged into it?
The most important component in your computer is the data that you put into it. If you lost any of the others it would be a simple matter of getting another lump of hardware. Sure, it might hurt a bit, but the fix is an easy one. Just replace the missing piece.
If you lose your data you not only have the problem of restoring the information, but frequently you don’t know just what you have lost. The importance of that little file of test data or the original of that letter you wrote nine months ago will only become apparent long after you’ve replaced the failed disc drive.
That’s why you should use Dropbox, Live Mesh or Skydrive (or all three if you have a lot of files you want to look after). These systems put your data in the cloud for you. Dropbox is good because it also does versioning, you can even recover when you damage a file by overwriting. The other two are good because they provide a bit more free storage. Google are also getting into the cloud storage act with Google Drive, which is available in the US but not the UK yet.
I keep all my files in the cloud. I can fit all my important documents and presentations into the few GBytes that they provide for free. All the above systems let me easily move my files from one machine to another, so if I get a new machine I just have to sign into the account for that particular service and then wait as all my files are magically loaded onto it. This makes the hardware pretty much incidental. I can use any machine to work on since the latest versions of my files will arrive from wherever I was working before. The decks I’m going to present on my “twisty top” tablet will move onto it in the time it takes me to walk to the lecture theatre.
All these systems are free and there is no excuse for not using them.