This wonderful image of The Andromeda Galaxy (also known as Messier 31) was taken by Sean Parker. According to his website, the total exposure time on the image was around 15 minutes and was obtained at the Kitt Peak National Observatory. Whereas the picture is taken in visible light, the long exposure reveals far more detail than you could ever hope to see with the naked eye.
You can buy a print of the image on his website, along with several more wonderful starscapes.
Fun fact: The Andromeda Galaxy is the most distant object you can see with the unaided eye. With a modest telescope or a decent pair of binoculars at a dark site, one could make out its elliptical shape. If it were bright enough to be resolved completely without photographic assistance, it would be five times larger than the full moon in the night sky.