Where can I go to get really cool desktop backgrounds?

Depends what you mean by "cool"





I dunno if this is what you're looking for, but you'll find a lot of pretty backgrounds by googling "abstract wallpapers"





here are two examples:


http://actualdownload.com/pictures/icon/abstract-screen-saver-1079.jpg


http://i262.photobucket.com/albums/ii117/SamuraiCow/AbstractWallpaperPurple.png





Hope this helps!