The presentation will be an invitation for expanding the repertoire of any computational chemist with research interests in electronic structure information, such as orbital composition (covalency), Coulomb interactions (effective nuclear charge), exchange interactions (spin polarization), for organic, inorganic, and organometallic compounds. The rainbow of X-rays employed in multi-edge X-ray absorption spectroscopy is an established high-energy physics technique for developing density functionals, refining empirical potentials for tight-binding methods, validating basis sets with high-level ab initio wave function methods, to name a few applications that we have been directly or indirectly involved through collaborations. Selected “classical” examples will be highlighted for the complementary information content of synchrotron-based spectroscopy in addition to hot-off-the-beamline results obtained at the Canadian Light Source during our May 2026 beamtime trip.