This talk will discuss PbCuTe2O6 which show properties compatible with a quantum spin liquid ground state. No long-range magnetic order or even static magnetism was observed down to the lowest temperatures in powder samples and the excitations are broad and diffuse quite unlike the spin-wave excitations of conventional magnets. Structural analysis and DFT calculations reveal that the source of the frustration is a 3-dimensional network of corner-sharing triangles due to the spin-1/2 Cu2+ ions and theoretical models shows convincing agreement with the magnetic correlations observed in neutron scattering measurements. More recent measurements have shown the presence of a ferroelectric transition below TC=1 K accompanied by a structural distortion. The transition depends on the grain size and is present in single crystals but suppressed in fine powders. Although this transition certainly complicates the magnetic properties of PbCuTe2O6 at lowest temperatures it does not give rise to long-range magnetic order.