Another really cool shot from Cassini of the low buzzing over Enceladus the other day. Not sure of the scale of this, but looks like a cold, rough place.
This is a mosaic created by Astro0 on Unmannedspaceflight. (Click for bigger view)
That geyser image from yesterday rates way up there on the coolness scale of space images. I think we have a 3 way tie between Apollo 8's Earthrise, and Phoenix on the chute.
I just have to share that MRO shot one more time. This is still my all time favorite so far.