Seerox

<p><a href="http://www.seerox.com/" rel="nofollow ugc">Seerox</a> brings another exciting plugin for you. This plugin will allow you to manage different file types in Media Library, So if you want to Enable/Disable any specific file type in media library to upload for Security reasons. Using this plugin you can control permissions for Your Site users to upload specific type of files not only from media library section but also from frontend.</p>
<h3>Features</h3>
<ul>
<li>Adds file extensions that WordPress doesn’t support by default</li>
</ul>


WP Media File Type Manager

WP Media File Type Manager will allow you to manage different file types in Media Library.

davide.airaghi

<p>This plugin let you add file types to the default list of file extensions<br />
supported by the Media Library upload procedure.</p>


WP Extra File Types


Works partially. With correct mime type, yes you can upload new files as "documents", but they are either refused in the end, or renamed into TIF extension if the mimtype is image.



impossible to insert them as attachement in a post.



there is a better plugin out there that creates posts for that purpose.


does not work, as expected

Plugin to let you extend the list of allowed file types supported by the Wordpress Media Library

WP Media File Type Manager vs WP Extra File Types