Fan art of PowerGirl, showing the inked and colored versions. Character owned by DC Comics.
Powergirl is one of the most popular characters drawn by pro-artist Adam Hughes.
More Classic Powergirl & Supergirl artwork below, by DSNG Artist [from the old DA gallery] and the last pic on the right is by Jim Lee:
Another Supergirl poster is over here: http://dsngsfm.blogspot.com/2011/04/supergirl-fanart-poster.html
And the Mighty Thor poster is over here: http://dsngsfm.blogspot.com/2010/11/mighty-thor.html
Browse through this blog [scroll to the very top and select the "Superheroes Fan Art" tab] and you'll find more cool posters...