HD Wallpaper: Minimalist Windows
Ratko Batinic is the designer who created the image and from his courtesy can be downloaded from here if you like it for personal use as desktop background and homescreen phone.
Widescreen Desktop / Macbook: 2560x1600 (fits on: 1920x1200, 1680x1050, 1440x900)
Samsung Galaxy Tab & iPad: 2048x1536 (compatible with many tablets)
HTC, Samsung Galaxy & iPhone: 900x1600 (compatible with many phones)