The clue is a Rubik's Cube with funny little dots on it.
Solving the cube (which you can do either the "normal" way or by
taking it apart and putting it back together) reveals that only the red, yellow,
and orange faces have dots on them. There is also the word "UP" printed on the
center blue face, and if you orient the cube with the blue face at the top, the
red, orange, and yellow faces look like this: