Les Harris

The Pressbox plugin adds a new tab to the Media Upload screen that allows you to insert images and files from Dropbox into your posts.
Additionally, the plugin provides a new shortcode that lets you add links or display images anywhere you want on your blog.
This plugin is under heavy development so please feel free to send me feedback, bug reports, and feature requests!
Credits:
This plugin bears a great debt to the work of Joe Doleson’s Wp To Twitter plugin for his excellent example of OAuth integration with WordPress.

Pressbox

Integrates DropBox with your blog allowing you to post images and files directly from your DropBox. Requires PHP 5.2 and cURL.

Chris Klosowski

Allows you to upload your themes CSS, JavaScript, and Images into your Dropbox ‘Public’ folder and server these files from the Dropbox network, reducing the bandwidth of your server and allowing users to load your site faster. Please note that as of now, this plugin only supports themes who use the filters ‘template_directory’, ‘template_directory_uri’, ‘stylesheet_directory’, and ‘stylesheet_directory_uri’ to determine the paths to the theme’s template and stylesheet files. I would only suggest this plugin for users who aren’t afraid of getting their hands a little diry.
This plugin is in no way affiliated with Dropbox.

Dropbox CDN

Use your Dropbox 'Public' folder as a free Content Delivery Network (or CDN). Please read the full description.

Pressbox vs Dropbox CDN