This very detailed simulation of large scale structure was created as part of the Illustris simulation. The distribution of dark matter is shown in blue and the gas distribution in orange. This simulation is for the current state of the Universe and is centered on a massive galaxy cluster. The region shown is about 300 million light-years across.
Illustration credit: Illustris Collaboration
Note: For more information, see Spooky Alignment of Quasars Across Billions of Light-Years.