Measurement of thermal and elastic properties of materials, like phonon density of states, specific heat or speed of sound, by a new X-ray scattering technique is presented. Inelastic nuclear resonant scattering of X-rays produced from new electron storage rings, coupled with advances in high-energy-resolution crystal optics and fast detectors has enabled the development of a new method of analyzing the energy loss in a scattering process with a resolution of 107 or better in the X-ray region of 6-30 keV. Some unique aspects like element (isotope) selectivity, the a-mount of material needed for analysis (nanograms) and physical size that X-rays can be focused (5 micrometer or better) favors this approach over more established techniques of neutron scattering, Mossbauer, and Raman spectroscopy. Applications to several unique cases (e.g., multilayers and high pressure) are discussed.