Photoactive smart polymers on surfaces are interesting in applications such as optical data storage and liquid crystal (LC) alignment.  In order to explore ultra-thin photo-addressable surfaces in these applications we have prepared high quality siloxane polymer monolayers using inexpensive and readily available new azobenzene trialkoxysilane precursors with butylamine catalysis.  High quality monolayers on glass prepared using this siloxane dye were characterized by several techniques.  Irradiation of these surfaces with plane-polarized visible laser light at normal incidence caused a rapid (microseconds) net orientation of the dye molecules such that the transition moment ends up preferentially perpendicular to the plane of polarization of the incident light.  This anisotropization of the surface was readily apparent in simple LC devices, showing a relatively rapid (seconds) and reversible re-orientation of the nematic LC director in parallel-aligned cells in situ, upon irradiation of the cells with low-intensity polarized light from an overhead projector or microscope illuminator.