Here is my second wallpaper using some of NASA's imagery. The last of the three will come late this evening. This one is based on an image of the Meathook Galaxy found on the Hubble Space Telescope's website. You'll find a 25.2 MB version on their site to download as well. Again, the detail in the photograph is stunning. Enjoy.
iPhone 4 (click image for full resolution to use as wallpaper):
Click below for the iPad version.