  A spectacular trick of close-up magicians involves the apparent passing of a
coin through a rubber sheet. The magic is based on the unusual elastic response
of a thin rubber sheet: the formation of an invagination, stabilized by
friction and elasticity, which holds the coin. By pressing on the coin, the
invagination becomes unstable, and the coin is released. We describe the
deformation analytically using a simple Hookean description, and examine the
stability of the invagination. We finally compare the prediction of the Hookean
analysis with numerical solutions of the neo-Hookean model, and provide a brief
commentary on the origins of the trick.
