 Besides symmetry-breaking phase transitions leading to magnetism, orbital and charge order, or superconductivity, correlations can also cause electron localization and many other striking many-body effects not described by the independent electron approximation.Entanglement of electrons in solids, in combination with details of the crystal lattice structure, produce a surprisingly rich variety of electronic phases, that are liquid, liquid-crystal and crystalline states of the charge and spin degrees of freedom.These complex electronic phases and the subtle competition among them very often give rise to novel functionality.