Back in the old forums, we had a thread dedicated to the showing and discussion of various artwork. In order to bring everyone up to speed, these are some of the top guys I've come across on deviantART. Obviously there are more, but these are one I was able to look up quick.
Anyway, a newer piece I wanted to show was from NuMioH. Amazing Dark Templar artwork. He took the idea of the Dark Templar using Zerg carapaces integrated into their armor and made it look far nicer than the older DT artwork we've seen. The armor isn't quite as bulky, and the Zerg armor is integrated with the Protoss armor. Very nice.