Snap, crack and pop: What elastic instabilities in toys can teach us

The mechanism of many modern toys rely on some form or other of elastic instability, from the locomotion of the ``Hexbug nano'' to the snapping of a ``Hopper popper.'' In this talk I will discuss some fundamental mechanical problems that are inspired by the mechanism of such toys. A particular focus will be on the ``snap'' and ``pop'' phases of the Hopper popper but I will also discuss the ``crack'' of a whip and other examples of dynamic elastic instabilities.