A review with 34 refs. covering history, synthesis, properties, and applications (neoteric solvents, extraction, solar batteries, radioactive waste treatment, etc.), and ionic liquids with an alkoxymethyl substituent. Of the many known, only very few liquids have been synthesized. Purification to yield specpure salts, methods to follow water content in ionic liquids, heat and mass transfer in ionic liquids etc. still remain to be studied and/or developed.