A 1x1 micron image of a monolayer of decanethiol self-assembled on a thin gold surface, taken by friction contrast with an atomic force microscope in contact mode. In the center, the atom-sharp tip has been used to paint a 200 nanometer square of fluorocarbon- terminated alkane into the layer, whose "slipperiness" compared to the surface plane is indicated by its lighter color. The individual grains of gold—randomly formed due to the heat of the deposition process—are visible. This image, taken under unusually excellent conditions, also shows the angstrom-scale "steps" characteristic of each gold grain surface.