I teach the MATLAB 101 class to every new hire at MathWorks. Inevitably, someone will ask me how to make a global variable. I then Google up: “How to make MATLAB Doug Cry” and find the above post. I think this is a post I should bring up every now and then because these things should be avoided today just like they should have been when I first wrote it.
I will be back from vacation soon with fresh content.