A speaker created by artist Dakd Jung, discovered by Gizmodo, visualizes music with ferrofluid, a liquid-filled with small magnetic particles. The ferrofluid, a viscous black blob, reacts to an electromagnetic device and dances around in synchronization with the sounds being played.
Ferrofluid was originally developed by NASA to move fuel into rocket engines without the aid of gravity. It did not work for that purpose, but it succeeded in looking cool as hell and having other practical uses. It can be used for speaker dampers, as a lubricant in ball bearings, or as a sealant in hard drives. One day it can even be used in biomedicine.
The liquid has been used to visualize music before, as in the video below, but having it in a closed container is much more appealing because it is a very messy substance. In addition, it’s just more fun to have a lava lamp that responds to your melodies than a tub of liquid that cools down next to the speaker system.