Extend the structure of the site by way of content models, data storage, field types, and navigation, so it is more understandable to users.
Menu Access Override provides a configuration option to menu items to allow them to be displayed regardless of a user's access rights.
Advanced Book Blocks integrates with the API provided by theJQuery Menu module to provide click and expand book menus with the ability to customize each block individually.
Update: Not tested but it looks like Double Field does what Text & Text does and more.
Drupal module for displaying embedded iframes from Crocodoc WEB API
Hide specific options of a select field for particular content type(s).
Term Info adds created, modified, author and published fields for terms.