Just have to share - Sisyphus Machine

Timelapse Sisyphus 1 from Bruce Shapiro on Vimeo.
Bruce Shapiro has invented the Sisyphus Machine, an elaborate kinetic drawing machine that uses magnets to drag rolling steel marbles through a thin layer of sand to create complicated mandala-like patterns. Shapiro, has spent 25 years experimenting with computerized motion control and many of his Sisyphus Machines have been installed in locations around the world including a large device in Switzerland back in 2003 and at Questacon in Canberra, Australia in 2013. The artist is currently working on a tabletop consumer version.