This two-tone pocket puzzle is classic in form and novel in function. When the silver and gold colored pieces are combined, they form a compact square with a plus sign subtracted from the middle.

Though the surfaces and the symbol of the puzzle are composed of right angles, once you begin to jangle the pieces apart, you will notice hidden notches which allow the elements to rotate and revolve in surprising new directions. A good choice for beginner to intermediate puzzlers.

This approachable design comes from Japanese inventor Edi Nagata.