Newgrounds.com, a site that used to be only for flash movies/games and music, has now added an art section.
Users can submit up to 20 works of art, and then if an established artist likes your work, they will add it to the gallery. The gallery has 5 sections: Ilustration, Fine Art, 3D Art, Pixel Art, and Other.
You can also choose to allow people to use your art for their works, like games or movies. Really just another way to get your art seen, and by possibly different people. I know some of you already know about it, because I've seen some recognizable art there. They also have a very nice upload/crop system.
Newgrounds News post about the gallery:
Newgrounds Pixel Art Gallery: