Here is a Google Documents plug-in for Ubuntu,to access your Google Documents on Ubuntu desktop via the default Nautilus file browser.

In Ubuntu 9.10 and higher,you can install this small plug-in by following commands in Applications->Accessories->Terminal:

sudo add-apt-repository ppa:doctormo/ppa 
sudo apt-get update
sudo apt-get install gdocs-mount-gtk

For Ubuntu 9.04 and earlier,you can add the source from this page:

After install gdoc-mount-gtk package in your Ubuntu,go to Applications->Accessories->Google Docs Connection.Input your Google Account and password,and then you should access to your Google Docs in pop-up file-browser:

Read more,click google-doc-mount