Quantum Mechanics (QM) is wonderfully non-intuitive and full of surprises. Most people think of QM surprises occurring for individual atoms but QM also provides unusual collective behavior in magnetic materials. Extreme QM behavior occurs in s = 1/2 antiferromagnets in low-dimensional (1D or 2D) systems. This talk will describe how the recent development of new molecular-based magnets is leading to observations of both predicted and unexpected quantum behavior.