Remember Douglas Adams' Ultimate Perspective Vortex? Where you get to see just how big you are in relation to the universe? The short sharp shock of reality which, of course, results in madness.
I regard any attempt to visualise the size of the universe as the cornerstone of realism, or spirituality (take your choice). Some kind chap at astrosurf.com sets out Spiritual Exercises for the 21st Century with a series of everyday analogies that only make it worse. Your chance to inwardly grow by attempting to understand what is beyond comprehension and picture what is beyond imagination. See you there!