sudo add-apt-repository ppa:gwendal-lebihan-dev/cinnamon-stableWhen logging in, click on the small Ubuntu logo, and select the desktop environment you want.
sudo apt-get update
sudo apt-get install cinnamon
I wish I had discovered this sooner. I've been using Unity for months and never did get used to it very well. I installed the Cinnamon desktop over the weekend, and it works like an old-fashioned desktop.