If you use MS SQL Express with the Ava application: as many of our customers do, SQL Express 2008 lacks a backup scheduler and email notification. For those "Oh f$%$^" occasions when you switch a computer on and it will just not start you need automatic backup. Occasionally a third party comes up with a product that compliments the Microsoft offering perfectly. This is one of those occasions: SQLBackupAndFTP does exactly what it says on the tin. It will back up your database on schedule, zip it up, copy it off site and tell you it's done it.
If you have a "small" number / volume of personal files (well less than 2GB!) you may want to share these between two or more computers or just simply back them up to avoid loss if you computer fails. This could be the office and home or office and laptop. There are quite a few free applications which do this. (There is a growing number) the ones we have some experience of are Dropbox, Sugarsync and Live Sync now called SkyDrive.
In this case Dropbox is a nice simple application that gives exactly this, for some reason the BBC's "Click" programme will mention dropbox, but not the (in our opinion superior Sugarsync). There is the inevitable Dropbox upgrade if you want more than 2GB.
We started with Dropbox, but because its a bit more flexible, far the best of these seems to be Sugarsync.
We no longer use Sugarsync. But that does not mean it will not work for you. We have some security concerns with many of these programs. Sugarsync also comes (now) with a 5GB free limit. It is more flexible than then equivalent release of DropBox. The version of DropBox we evaluated did not allow syncing of files outside the DropBox folder. SugarSync allows any folder to be chosen and synced with any other folder on another machine. So C:\important stuff on one machine can be synced with E:\copy\of\important\stuff on another machine. Which is very useful when syncing a laptop with 2 small drives and a desktop with one large drive. There are versions which allow you to sync file to your iPhone, Andriod, Blackberry, Windows 7 phone etc. You can choose to sync different combinations of folders to each individual device.
Another alternative (from Microsoft this time) is Live Sync now called Sky Drive. (You'll need to set up a free windows ID first)
So that is 9GB of data you can store on the web for free!!!
There is a more recent appraisal of free and paid backup cloud services here.
And an even more recent appraisal including Google drivehere
Ok these articles just keep coming cloud drives/