See also, http://www.ribbonfarm.com/2009/10/07/the-gervais-principle-o... - along similar lines, even if it's not a 2x2. It's doubtless been on HN numerous times, but if you haven't read it before then it might, at the very least, pass the time.

(The ribbonfarm guy likes 2x2 diagrams as well: http://www.ribbonfarm.com/2009/04/20/how-to-draw-and-judge-q...)