For Willem, obviously:

Gabriel Orozco, ‘Pendulum’ (19??)

Pendulum is an oval billiard table, with the middle ball swinging back and forth, suspended from a string.

Orozco’s sculptural works are often themed around the idea of play, obstructing the actual element of play by adding symmetry.

‘Ping pond table’ (1998)

The ping pond table is a lily pond, surrounded by ping pong fields.

A lot of people will know Orozco from this work:

Work by Gabriel Orozco can currently be seen at the Stedelijk Museum Schiedam (not to be confused with the Stedelijk that’s currently in crisis).