The Hubble Space Telescope took an amazing picture the other day - actually it took 11.3 days of exposure time, taken over the course of 400 Hubble orbits. This image - called the Ultra Deep Field - contains about 10,000 galaxies, cutting across billions of light years. "In ground based photographs, the patch of sky in which the galaxies reside (just one-tenth the diameter of the moon) is largely empty."
(click image for full-size interactive viewer)
Be sure to hit F11 to maximize your browser's window so you can see as much of the image as possible.
As usual, I upsampled the image and am serving it with Aperio's image server software.