The present generation of X-ray telescopes emphasizes either high image quality (e.g. Chandra with sub-arc second resolution) or large effective area (e.g. XMM-Newton). Several technologies under development (e.g. slumped glass, pore optics) aim to greatly enhance the effective area, while maintaining moderate ( 10 arc-seconds) image quality. The direct deposition of piezoelectric thin films on thin substrates, under study at Smithsonian Astrophysical Observatory, offers an appealing technology for the realization of lightweight adjustable mirrors capable of sub-arcsecond resolution. This solution will make it possible to realize X-ray telescopes with both large effective area and exceptional angular resolution and, in particular, it will enable the realization of the adjustable optics for the proposed mission Square Meter Arcsecond Resolution X-ray Telescope (SMART-X). In the past years we demonstrated for the first time the possibility of depositing a working piezoelectric thin film (1-5 um) made of lead-zirconate-titanate (PZT) on glass, showing a good correspondence between the theoretical and measured behaviour of mirror samples. The status of the technology and the recent progress are here presented.