Hello there
This map was done for the june challenge with the intent to depict an underwater landscape, and because i like space maps there's also a few stars on the map.
I've used QGIS for the topography, sketchup to add cities and space station, and photoshop/illustrator to polish the final render. the background is a composite of NGC 602 and other nebulae.
Click image for larger version. 

Name:	RENDU1.jpg 
Views:	331 
Size:	2.51 MB 
ID:	116478
Critics are welcome to improve future maps, i know the background on this one is a bit too strong, but i can't stop myself from adding star backgrounds