Ferrofluid: Ever played with a magnetic liquid?

Ever played with magnets in your childhood? I am sure the answer will be a YES. With the progress in science and technology over the ages, researchers have developed many astonishing stuff in the field of Physics. But what if the magnets you payed with turn into a liquid?????
Have a look into this short video to have an idea about Ferrofluids

Ferrofluid: A combination of ferromagnetism and liquid; which becomes strongly magnetized in the presence of a magnetic field.

Source: Technology and Tools/Youtube