I shot it with a Nikkor 10.5mm fisheye lens, using a preset white balance. I used DxO optics to de-fisheye the image, tweak the exposure etc, reduce noise and to apply a more balanced, sodium lamp white balance. Then I added a slight blue-cast in Aperture.
A shot with the same processing, but without the blue-cast is this one.
I thought the reduced colour range from the blue cast would make it less distracting as wallpaper, seems to work!