Peekaboo! Cassini recently captured a series of images documenting Rhea passing behind Titan. I love how Titan's smog discolors Rhea's surface. Though, to be honest, the color in this image is fiction, based on truth. The image sequence was only captured through a clear filter, but Gordan Ugarkovic used another color image of Titan to artificially colorize this cool view.
NASA / JPL / SSI / colorization by Gordan Ugarkovic
Titan and Rhea
On October 27, 2009, Cassini caught Titan passing in front of the icy moon Rhea.