This is a really nice easy plugin, even given that I don't understand CSS! I pasted it into the stylesheet and it works!
However, I can't revert to full width text after using some columns. ie. I want my middle part of text to be in two columns, but the finishing paragraph to be full width again. It's not possible...the text just keeps on flowing down the last column.
So...how do you 'escape' columns after using them?