Attended a workshop today and found out about Dropbox from one of the guys. I have been using iDrive to backup my files at home for quite sometime now. I haven't had any problems but there are a few drawbacks of the service. Fist of all, it takes ages to save a few MBs of files. Further more, there were problems when you tried to access the account form another computer.
So when I found out Dropbox and it's features, I was quite excited. Go to the site, install the application on your PC or laptop and then sign up. You get just 2GB for the free version but that's quite good enough for me. However, you have the chance of upgrading the space up to 8 GB by recommending friends.
After installation, you will see a box icon in the task bar below. Clicking on it will bring up the Dropbox folder. Just drag or save stuff there like you would normally do. The files automatically get saved and you can access it form anywhere with an internet connection. You can also share files with other people as well.
Just found out that there is a Dropbox App for the iPhone and you can actually edit your documents on the iPhone using Quickoffice.