It really depends on what your standards are for a vacuum. If you think that the quantum foam makes space not a vacuum, then there is no vacuum. If you aren't concerned about that, but do think that photons, neutrinos, and virtual particles do count, then there are very tiny short-lived vacuums. If you count matter densities of a few nuclei per cubic centimeter as close enough, then the universe contains mostly gigantic vacuums between the galaxies.
Originally Posted by Laminal Cockroach
Forming opinions as we speak