Ferrofluid

Ferrofluid is a liquid which becomes strongly polarised in the presence of a magnetic field. This is stuff is pretty amazing. It appears as a dark black liquid until magnetized, where the liquid forms rigid shapes that can be manipulated.
Some everyday uses for this liquid are car suspension, RAM paint for the Air Force, Medicine and heat transfer technology.

Here are some art applications:
Sachiko Kodama Video

Shawn Knol Video


This technique was also used in the rider titles in the new Alien Workshop video, Mind Field.