We discuss the recently published Cornell HI archive, a homogeneous compilation of HI spectral parameters extracted from global 21 cm line spectra for some 9000 galaxies in the local universe obtained with a variety of single dish radio telescopes (but for which the largest contribution comes from Arecibo) but reanalyzed using a single set of parameter extraction algorithms. Also discussed are two scientific applications of the data in the archive. We have used a complete optical diameter and HI flux limited subsample of the catalog to derive the HI mass function (HIMF) for masses log(M_HI/M_Sun)>7.4 which takes into account the effects of local large scale structure. We find marginal evidence to suggest that the HIMF has a shallower slope in higher density regions than lower density regions. We have also combined the HI archive with a separate compilation of optical photometry and spectroscopy to generate a catalog of Tully-Fisher distances and peculiar velocities, the SFI++. Using this catalog, we have examined the peculiar velocity field in and around the Pisces-Perseus Supercluster (PPS). Comparing the SFI++ velocity field to the field predicted by PSCz, we find less correlation between observed and model velocities for the PPS subsample than in the rest of the sky.