I've mentioned the stellar service Dropbox provides in the past.
If you aren't familiar with it, Dropbox puts a folder on your desktop and anything you put in that folder is automatically backed up online. You can also connect that folder to another computer and the files and folders placed in it will automatically sync between the computers. All your files are available through any web browser. You get 2 GB free.
It turns out they have a referral program where if you sign up by clicking HERE you get 10% extra space on the free version (and I get the same amount added to my account).
Give it a try. Install it on your work computer and your home computer and watch the magic happen. It works on Mac, Windows and Unix. Even if you don't need to sync files between computers, it's still a great, simple way to get 2 GB of easy-to-use, easy-to-access, always available (even when you're offline) online backups. It also includes a great online interface so you can access your files from any computer with Internet access.
Just sign up already, OK?