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Surface brightness fluctuations in E-S0 galaxies are sufficiently bright in the infrared that they can be recorded with high signal-to-noise in galaxies within 80 Mpc in a single HST orbit. The SBF luminosity dependence on metallicity and age tracked by color is well established comma permitting measurements of individual distances accurate to 5%. This outstanding capability will be used to determine distances for SNAP targets drawn from every massive cluster and the most important E-S0 galaxies outside of massive clusters within 80 Mpc. Galaxy-galaxy and galaxy-cluster comparisons with elliptical fundamental plane comma spiral luminosity-linewidth and comma especially comma supernova distances will be made whereever possible in order to evaluate random and systematic uncertainties. SBF can provide distance measures for the cosmological measurement of H0 comparable in accuracy to those of SNIa. SBF anchored by the tip of the red giant branch zero point offers a competitive and independent alternative to the Cepheid-SNIa route to H0. The most massive clusters at 40-80 Mpc lie within either the so-called Great Attractor region or the Perseus-Pisces filament. This range is the sweet spot for HST IR SBF studies - distances too great to be reliably measured from the ground but comfortably accessable with HST in single orbits. The dynamics in these two complexes are in the strongly non-linear regime with clusters collapsing toward each other. Numerical action methods will permit the recovery of physical orbits and the determination of masses. The 3D information on positions and motions affords a unique window into the construction of rich clusters.