Got started with using code.google.com project hosting for ngwallpaper project. When you execute this python script, it fetches the wallpaper of the day from National Geographic site and sets it up as your Desktop Wallpaper.
Currently works on Windows platform with python windows extensions installs ( it uses SETDESTOPWALLPAPER attribute of a particular windows call).
Desirable features for ngwallpaper is 1) Platform agnostic (Windows, Linux, Mac) 2)More structure code. One present is just a start version 3)the program as a service or scheduled service which will run a particular time everyday. 4) Fix the windows set wallpaper issue where after few hours the wallpaper gets reset.