I've been wanting to depict Phobos from that angle for a long long time...
In case you don't know, Phobos is the main moon of Mars (the other being Deimos) and rotates close to Mars (about 9,400 km from its surface - considering Mars has a diameter of 6,779 km), which means when on Phobos, you would have a majestic sight on Mars. Also, Phobos has almost no gravity, which means you could almost approach it as an asteroid, which differs a lot from approaching our Moon.
I've worked around 6 hours on this photomanipulation, made with Gimp (+ a 3D sphere mapping of Mars with Blender).
All on Linux-Ubuntu.
ENJOY IT IN HD on my DeviantArt gallery.