Ubuntu One is a good possibility to save your files. It's a free online harddisk. It offers 2 GB hard disk space.
If you like more space you can buy up to 50 GB. To use Ubuntu One you need a LanuchPad Account, you will get this account when you use the first time Ubuntu One.
Applications -> Internet -> Ubuntu One
It's also possible to share your files with others and you can access to your files from other computers.