How to Do a Matrix Reshape by 'blocks'

(Originally posted on Doug's MATLAB Video Tutorials blog.)

This week's video covers a non-standard way of reshaping a matrix. Instead of using the reshape function, this kind of matrix manipulation must be done with for loops. This matrix reshape operation treats submatrices within the original matrix as a unit. I suspect there are many other ways of doing this, and would love to hear about them in the comments.