Executive toy is a useless, but stylish and funny accessory usually placed on the desk of a corporate executive. The best known are
  • Kinetic Balls, where a bunch of balls are suspended from above, one is pulled from the rest and kicks them, transferring the kinetic energy to the last one.
  • Perpetual pendulum, a pendulum that doesn't stop thanks to an electric magnet in the base of the toy.
  • Pin Art, a box with thousands of small pins of equal length inserted into a board, that can be pressed from one side with any object so that other ends of the pins form the same object on the other side of the board.

You can see some pictures (they have Kinetic Balls and Pin Art) at http://www.desktoy.com/

The first executive toy was probably a gadget designed by the great mathematician and engineer Philon of Byzantium (about 280 BC - about 220 BC). It was an octagon-shaped ink pot with openings on each side. One could turn the pot so that any face is on top and dip the pen in the opening, but the ink never ran out through the holes on other sides. The inkwell was suspended in the centre on a series of gimbals and remained stationary in spite of any rotation.

Source: Piter James, Nick Thorpe. Ancient Inventions.