Physics cornucopia (physicopia?)

You know my eclectic file of intriguing news from the world of physics, into which I dip from time to time? Well, that file (metaphorically speaking, anyway) is bulging. Which gives us this week's topic.
You know all those tidy equations we learn in physics classes? They often deal with idealized situations, like friction-less planes. The real world tends to the chaotic.(*)
(*)  To physicists and mathematicians, "chaos" has a precise meaning: dynamic, generally nonlinear, systems that are...