On the MacBook Pro, Command+S saves the notebook. So, every few minutes, Command+S is invaluable.
What do other folks do? For example, in TexShop, when I compile my LaTeX code, the file is automatically saved. Is there such a feature for notebook and/or cell evaluation? What are my options?
It's pretty horrible if you haven't saved your work and Mathematica crashes. This is certainly something I would want to share with my students as well.