  The global missing baryon problem - that the sum of observed baryons falls
short of the number expected form BBN - is well known. In addition to this,
there is also a local missing baryon problem that applies to individual dark
matter halos. This halo by halo missing baryon problem is such that the
observed mass fraction of baryons in individual galaxies falls short of the
cosmic baryon fraction. This deficit is a strong function of circular velocity.
I give an empirical estimate of this function, and note the presence of a
critical scale of ~900 km/s therein. I also briefly review Omega_b from BBN,
highlighting the persistent tension between lithium and the CMB, and discuss
some pros and cons of individual galaxies and clusters of galaxies as potential
reservoirs of dark baryons.
