Although the C-H...O hydrogen bond is practically ubiquitous in supramolecular assemblies, findings of corresponding C-H...N bridges have so far been comparatively rare. The crystal structures of four related, novel co-ordination polymers involving R3Sn+, [M(CN)(n)](m-) and nBu(4)N(+) ions as essential building blocks have been examined in view of the involvement of C-H...N bridges between any of the alpha-CH2 groups of the nBu(4)N(+) ions and N atoms of the CN ligands. Distinct C-H...N bridges with (in part) unprecedentedly short C...N contacts (down to 317 pm) have in fact been found, primarily with cyanide N atoms not engaged in simultaneous N --> Sn bonding. Another cation that turns out to be capable of forming significant C-H...N bridges even with metal-bridging CN-ligands is the complex [Co-III(C5H5)(2)](+).