wallpaper-changer
This script updates my Dropbox with a current picture of NYC from the Westin Hotel website, which I then use with GeekTool to update my wallpaper every hour.
It uses https://github.com/FbF/Instafilter for the filter, and the common Dropbox API for uploading. The dropbox.php file is ignored because it's a custom function containing my access token, folder structure and the like.