Desktopia
Visual Paradox
Free Nature-Animal-Butterfly-Flower Wallpapers
Billy-Bear's Zoo of wallpapers
3D Art Wallpapers (Warning some pop-ups)
3D Art Fantasies
(R) for Rock, (C) for Colorful
(R) Copy the exacts same thing as the last one!
(R) Superior Pics
(C)Google image search for "Colorful Badgrounds"
(C) Istock
(C) Thunder Promotions (sucks...can't steal them.)