Electrical characterization of materials has undergone significant progress recently, with the development of a number of atomic force microscopy (AFM) techniques. In the report is described a new variant-conducting probe AFM (CPAFM)-which uses conducting probes to measure current-voltage relationships and resistances, and which is reported to be ideal for studying electrical transport on nanometer length scales, in particular for the characterization of organic thin films. Highlights of recent CPAFM measurements on extremely thin crystals of sexithiophene are presented.