I use just about every image under the search "fav:OOZ662 rating:s -flash height:>600 width:>800 -comic" as backgrounds. Just have to use Windows 7's "Personalize" menu theme-maker thing to make a custom background slideshow. A lot of people are too picky about borders and letterboxing to handle having such random sized images as their backgrounds, though. Especially people who use bigger resolutions.