Spin is an intrinsic quantum degree of freedom for various elementary particles that together make all of matter in our Universe. A salient feature of spin is its polarizability when subject to external probes such as a magnetic field. This feature is at the heart of many interesting phenomena across different disciplines of physics. In this talk, I will briefly recount some of those examples and then tell the latest fascinating story of spin from nuclear physics research, and more specifically from a new phase of nuclear matter called the quark-gluon plasma (QGP). This subatomic quantum material occupied the baby Universe briefly and is re-created today in laboratories through high energy nuclear collisions. Two decades of comprehensive studies have found the QGP to be an extreme fluid in several aspects, as I shall show you. It is only in recent years that physicists have started to unravel novel effects arising from the interplay between particle spin and the extreme conditions available in a QGP droplet. I will discuss how the polarization of spin by chirality, vorticity and magnetic field leads to nontrivial signatures that can be observed experimentally.
