Here is what my Macbook Desktop looks like:
My iMac desktop in my office also looks exactly like the above. In fact, when I create a file on my Macbook desktop at home, it magically appears on my iMac desktop in the office.
My desktop now lives in the Cloud, thanks to Google Drive. There is no "special folder" that I have to remember putting my files into for them to be synced across all my machines.
How did I do this? Read on!
First, you have to install Google Drive. Go to http://drive.google.com and log into your Google account. Click on the "Get started with 5 GB free" button on the top.
Launch Google Drive from your Application Menu (or Launchpad on OS X Lion) and sign in using your Google account.
Next, launch a terminal and change your Desktop to use Google Drive instead as follows:
$ mv Desktop/* Google\ Drive/
$ rm -r Desktop
$ ln -s Google\ Drive/ Desktop
Log out and log back in.
Now your Desktop should start syncing and showing all your files in Google Docs. Any new files or folders that you create in your Desktop from now on will be synced across all machines that have Google Drive set up.
Repeat the aforementioned instructions for all machines which you want to keep in sync and enjoy the ride!