Dropbox

Dropbox is a cloud-based file backup, storage, and sharing site which uses Amazon's S3 service as the backend.  I've recently started using it as a way to keep certain files and folders automatically synced between my MacBook Pro and Hobbit, my MSI netbook.

You can access a Dropbox account via a web browser or applications which install on Mac OS X, Windows, or Linux.  So far, I'm using the OS X and Ubuntu versions and they work very smoothly.  On a Mac you can access your Dropbox folder just like any other folder in the Finder.  On Ubuntu, I'm using the Nautilus file manager plugin.

If you allow the Dropbox app to run automatically when you login, it will automatically sync the local folder with the one in the cloud.  If you have Dropbox installed on more than one computer it will automatically sync the folder across all of them.

The free, basic Dropbox account gives you 2 GB of storage.  Additional storage is available for a monthly fee.  {shameless plug}Also, if you sign up by clicking the links in this post or in my sidebar to the right, I'll get an additional 250 MB of space (up to 8 GB), and you'll get additional space, too.{/shameless plug}