There are never enough wallpapers!
I don't know about others, but I am partial to images of the sky. Maybe others like them too: that's why I have made available several photos of the sky, with clouds, at twilight, at sunset, or foggy. You can find them on Flickr, in the photo set Wallpapers. All images have 1920×1200 pixels. I recommend to set the display option of the wallpaper to "stretch", i.e., fill the screen disregarding the aspect ratio -- in the end, the clouds could well have had any shape.
Once you have found a wallpaper that you like, you will probably want to download the full-resolution photo. In order to download the full-resolution photo at 1920×1200 pixels you must first press the "Actions" button; this will display a menu. Then you must choose "View all sizes"; this will display a new Web page where you will be given the possibility to download the original image.