Rubik's Cube
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Rubik's Cube

"3-D combination puzzle invented in 1974 by Hungarian sculptor and professor of architecture Ernő Rubik." --wikipedia
Rubik's Cube

cal. 395

Level of arithmetic, recreation and happy (TvF).

Wikipedia says:

By 1981, Rubik's Cube had become a craze, and it is estimated that in the period from 1980 to 1983 around 200 million Rubik's Cubes were sold worldwide.