Im not sure wether ferrofluid qualifys for electronics but Its very cool. Has anybody ever bought any ferrofluid? Ferrofluids were discovered at the National Aeronautics and Space Administration (NASA) Research Center in the 1960s. NASA scientists were investigating different possible methods of controlling liquids in space. NASA scientists discovered that they could precisely control the location of a ferrofluid through the application of a magnetic field. Additionally, by varying the strength of the field, the fluids could be made to flow.
Its really amazing. If you hold a neodymium magnet over a dish holding it, the ferrofluid will jump out! And if you hold the magnet under the dish the magnatite particles will line up and create spikes.