Upload Files to DropBox with only JavaScript and HTML 5
This is based on the work of Dave Mello who wrote a previous dropbox uploader that can be found here: http://www.newfangled.com/direct_javascript_dropbox_api_usage
and Eric Bidelman who wrote an HTML5 file uploader that can be found here: http://www.html5rocks.com/en/tutorials/file/dndfiles/
Both gentleman wrote very nice tutorials. Read them.
To use this demo you will need to set up a Dropbox app with a developers account and add the app key on line 86 of reader.js. Enjoy.