The ConceptartWorld site has become one of my favourites as it brings together work from around the net and that work is inspirational stuff indeed.
Bulletstorm concept pieces from the team at People Can Fly. I love the character designs, the detail in how their pants, belts, buckles and equipment all mesh together with all the varying materials etc. The artists also bring specific character traits to life for us, seemingly effortlessly - but doubtless it takes time and practice. How good does Trishka look - see more on ConceptartWorld
[Bulletstorm concept art via the conceptartworld]
Emrah Elmasli's concept art for Fable 3 shows off the high fantasy styling and again brings alive some complex and emotive costume designs for the various factions. This strong design ethic that binds together the cultural look and feel of characters, races and groups in games like these gives each a strong identity and builds clever responses to each decision around designing for them.
[Fable 3 concept art via the conceptartworld]