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The scale of the features to be imaged with HESSI requires an angular resolution of two arcseconds.  This means being able to see a penny at a distance of over a mile in X-rays and gamma rays.  HESSI achieves this feat by using gold and tungsten grids with extremely fine slits, some as fine as 20 microns wide (less than one thousandth of an inch).  The manufacture of these grids has been made possible by newly developed microfabrication techniques.  In addition, the mission requires the use of segmented, hyperpure germanium detectors, with a recently developed electro-mechanical cryocooler to maintain them at an operating temperature of minus 198 degrees Centigrade.  Both developments have potential applications in medical, industrial, and nuclear X-ray and gamma-ray imaging/spectroscopy.  Potential applications for the fine grids include X-ray imaging for high-volume baggage inspection, characterization of heavy metal deposits, radioactive waste assessment, and a micro mass spectrometer.