A close friend just lost all her data thanks to a hard drive crash. Luckily, she only had 6 months or so of data that wasn’t backed up and has now learnt a harsh lesson – hard drives always fail. It’s a question of when, not if.
So, how do you get prepared? Here is my suggested approach.
Step 1 – Prepare a list of the data that you absolutely need backed up. Think key documents, pictures, music, etc. Then think about whether some of this data can be recovered – e.g. if you buy all your music on iTunes, it can be downloaded pretty easily. Movies, on the other hand, might take a bit longer but this can still be done.
Documents and pictures, however, are probably much harder to recover.
Step 2 – Use Dropbox or Sugarsync for all your documents. Dropbox gives you 2 GB of free space with multiple add ons (I have 8.63 GB thanks to various space handouts) and Sugarsync gives you 5 GB. This should more than suffice for all your documents.
I would suggest moving all your document folders onto Dropbox/Sugarsync or both. This way, you never have to worry about your documents being lost. The moment your document is saved, Dropbox makes a copy on the cloud that you can access on Dropbox.com wherever you are.
Step 3 – If you value photos, invest in a cloud based back up solution for photos. I invested in CrashPlan a few weeks back. It is a unobtrusive service that runs in the background. I am backing up all my pictures and outlook data files onto Crashplan right now and am looking forward to not worrying about hard drive crashes in a few days.
CrashPlan+ is a great deal for 9 computers and costs roughly $1/month/computer if you find family and friends to share it with. A low price to pay for peace of mind. If you’re looking for company, please let me know and I’ll be happy to share a couple of empty spots on my plan.

Step 4 – Back up all this stuff onto an additional hard drive anyway. Never hurts. Do it but don’t rely on it.
Hope it helps!