Nanostructures down to a few nanometers in size and composed of close-packed and well-ordered molecules have been fabricated by simultaneous nanoshaving using an atomic force microscopy (AFM) tip and alkanethiols' self-assembly on gold. Compared with other microfabrication methods, this procedure allows more precise control in terms of the size and geometry of the fabricated features. An edge resolution better than 2 nm can be routinely obtained. In addition, the fabricated nanostructures can be quickly changed, modified, and characterized in situ. These advantages should make this method very useful in the development of prototypical nanoelectronic devices and, perhaps more importantly, in the study of spatially confined chemical reactions.