Liquid-liquid phase separation by macroions fascinated mid-century colloid chemists. Modern techniques now illuminate those old Dutch and Russian research gems, and explain why polyelectrolyte-protein and polyelectrolyte-micelle coacervates exhibit compartmentalized enzyme activity and immobilized detergency, respectively. SANS, DLS, rheology, FRAP, Cryo-TEM and TIRF show that microscopic heterogeneities in these macroscopically homogeneous fluids provide transient gel-like properties.