(N.B. This should also work on Linux Mint 14/15)
Unfortunately, because Netflix streaming is powered by Silverlight and not Flash, it is not officially possible to watch Netflix movies on Ubuntu, or any other Linux distribution for that matter, because Microsoft does not provide a version of Silverlight for Linux. And I say officially. Because someone has made it incredibly easy to watch Netflix movies on Ubuntu by pre-packaging all the software necessary to get Netflix working - a patched version of Wine (a compatibility layer for Windows software), Firefox for Windows, and v4 of the Silverlight plugin. The result - Netflix working great on Ubuntu. Of course the quality and stability of the video isn't as perfect as watching Netflix on a Windows or Mac computer, but the bottom line is, it works - and it works pretty well!
So how do I get Netflix working on Ubuntu?
Really easily. Just open a Terminal window (from the Dash or by the keyboard shortcut Ctrl + Alt + T) and execute:
sudo apt-add-repository ppa:ehoover/compholio
This adds the PPA that is the repository which has the packages (the software) which the author of this solution had created and packaged. Next, let's install Netflix:
sudo apt-get update && sudo apt-get install netflix-desktop
And that's it . Enjoy watching Netflix on Ubuntu! Simply find Netflix from the Dash as if it was a dedicated desktop app. You can also lock the Netflix app to the Launcher.
If you ever want to uninstall it, simply execute:
sudo apt-get remove netflix-desktop
sudo apt-get autoremove
sudo add-apt-repository --remove ppa:ehoover/compholio