In the continuing search for new physical properties and combinations of properties in molecular materials, novel phenomena and structures are identified in three categories of TTF and BEDT–TTF (bis-ethylenedithiotetrathiafulvalene) charge-transfer salts with inorganic complex anions. When the anion is a 3d complex containing NCS– and an aromatic donor, long range π–d ferrimagnetic order is established by donor-anion π–π overlap; when the anion is a tris-oxalato-metallate(III) complex, both normal state and superconducting behaviour are dramatically influenced by changing guest molecules in the lattice, while incorporating columns of crown ether and H3O+/H2O leads to metallic conductors that simultaneously transport protons. To cite this article: P. Day, C. R. Chimie 6 (2003).