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This is the story of a crystal structure of a largely hydrophobic cyclic peptide which crystallizes with 12 water molecules located in a central channel. At -80 C, the water structure is ordered (including H atoms) and contains 4- to 7-membered rings with a central 6-ring backbone (as in hexagonal ice) and a semi-clathrate structure to accommodate a protruding methyl group. As the crystal warms, certain hydrogen atoms begin to "move": Others follow at higher temperatures. By 0 C, the hydrogens are no longer localized, but the oxygen atoms are still quite visible and still ordered. At ca 4 C, there is a phase change in which the 6-membered ring begins to "melt". Interesting fundamental problems of this sort can also be effectively studied with synchrotron radiation. Synchrotrons were originally built by and for physicists, but in the last decade all branches of science have begun to use these sources, drawn in by the availability of near laser-like beams of photons and the construction of dedicated beamlines with automated "familiar" instrumentation. Among the "outside" users taking advantage of these facilities are: powder diffractionists who are determining structures of new compounds ranging from drug candidates to superconductors; protein crystallographers who are not only using the brilliance to get data from small crystals but also using the tunability to solve structures via MADD procedures; small-molecule single-crystal diffractionists who are using the very short wavelengths to minimize absorption effects and to obtain high q data for electron density analysis; spectroscopists are using EXAFS and XANES for the in-situ characterization of the local environment of atoms in catalysts or for the identification environmental hazards. This talk will also give an overview of recent activities at Brookhaven's NSLS and Argonne's APS synchrotrons in order to stimulate excitement in those researchers not already familiar with the benefits of synchrotron x-radiation as compared with in-house facilities.