Xavier Media

This plugin will do a backup of your WordPress database and, or your files in wp-content/uploads and saves 
it somewhere safe. You can have the backup saved in your <a href="http://db.tt/9Jo39Xy" rel="nofollow ugc">Dropbox account</a>, a FTP account of your choise, your 
account with <a href="http://www.securepaynet.net/email/online-file-storage.aspx?ci=1796&prog_id=xaviermedia&isc=xmbackup" rel="nofollow ugc">Online File Folder</a>, or have the backup emailed to you (not recommended for large files). You can 
select to have the backups named the same every day or to have a date added to each file name.
This plugin requires PHP, cURL, PHP compiled with ZIP support, and Oauth (for Dropbox).
** NO WARRANTY SUPPLIED! **
** Make sure you test your Backups! **

XM-Backup

Does a backup of your Wordpress database and, or your files in wp-content/uploads and saves it in a safe location.

Blighty

This plugin allows the complete file structure of a folder in Dropbox to be shared within a WordPress page or post. The folder can then be navigated via the WordPress site and files selected and downloaded. Changes in the Dropbox folder, such as the addition or deletion of files, are reflected through to the WordPress site.
<h4>Features</h4>
<ul>
<li>Shows a folder/file navigator that mirrors a folder in your dropbox account.</li>
<li>Optionally display file size and file date in the folder display.</li>
<li>Allows for file uploads, either to a dedicated hidden folder, or to the currently displayed dropbox folder.</li>
<li>Allows access rights to be set on each top-level subfolder.</li>
<li>Compatible with most lightbox-type image plugins.</li>
</ul>

Blighty Explorer

Allows the complete file structure of a folder in Dropbox to be shared and navigated within a Wordpress page or post. It also allows for file uploads.

XM-Backup vs Blighty Explorer