A Sampling of Videos from the N-Body Shop
The formation of a Milky Way mass galaxy. Green-grey = gas, blue/red = stars. This simulation contains the gravitational influence of Dark Matter, but it is not shown in this movie. The frame is roughly 30 comoving kpc across.
This simulated Milky Way-mass galaxy has been post-processed to "observe" the stellar light in the Sloan Digital Sky Survey's g, r, and i filter bands. As the galaxy passes edge-on, light from the stars is absorbed by dust in the gas, out of the line-of-sight. This galaxy has been superimposed on a background of both real SDSS galaxies and more simulated galaxies.
The formation of cosmic structure in a 50 Mpc (comoving) volume.
The first-ever simulated bulgeless dwarf galaxy. Originally published in Solving the Cold Dark Matter Small Scale Crisis by Forming Bulgeless Dwarf Galaxies, 2010, Nature, 463, 203, arXiv:0911.2237
See more fantastic animations by Andrew Pontzen at his youtube channel.