Jennifer M. Dodd

This plugin creates a user-object relationship table and a user-object relationship metadata 
table. Relationships between a user (logged-in or IP) are created and added to the relationship 
table; metadata (ex. votes, flags, and ratings) is attached to that particular relationship 
via the metadata table. This is a framework; it is intended for use in voting, flagging, 
and similar user applications where a user-affiliated metadata is attached to an object. 
Supported object tables include wp_posts, wp_comments, wp_users, and wp_bp_activity.
Functions are provided to add/get/delete relationships; metadata is added via the native WordPress 
metadata-handling functions. 
Functions provided by this framework include:
<ul>
<li><code>ucc_uof_object_reference()</code> returns an array of object-integer assignments. Use this to look up the 
appropriate value for $object_ref based on the object table (wp_posts, wp_comments, wp_users, 
wp_bp_activity are currently supported) to which you are attaching a user relationship.</li>
<li><code>ucc_uof_add_relationship( $user_id = 0, $user_ip = 0, $object_id, $object_ref )</code> adds a relationship 
to the relationship table if none exists and returns the relationship id for that user/object pairing.</li>
<li><code>ucc_uof_delete_relationship( $user_id = 0, $user_ip = 0, $object_id, $object_ref )</code> will delete a 
relationship if there are no metadata entries left for that relationship.</li>
<li><code>ucc_uof_get_relationship()</code> returns the relationship id for that user/object pairing.</li>
<li><code>ucc_uof_get_user_id()</code> returns the current user id or 0 if not logged in.</li>
<li><code>ucc_uof_get_user_ip()</code> returns 0 if the current user is logged in, or an ip2long() if anonymous.</li>
</ul>
Example code:
<pre><code>// Create or get the user-object relationship.
$relationship = ucc_uof_get_relationship( $user_id, $user_ip, $object_id, $object_ref );
if ( empty( $relationship ) )
 $relationship = ucc_uof_add_relationship( $user_id, $user_ip, $object_id, $object_ref );

// Add user_object_meta.
if ( $mode == 'delete' )
 delete_metadata( 'uof_user_object', $relationship, '_your_meta_key' );
else
 update_metadata( 'uof_user_object', $relationship, '_your_meta_key', 'your meta key value' );
</code></pre>

User Object Framework

Provide a framework for assignment of user-object relationship metadata.

Automattic

Donncha O Caoimh (a11n)

Michael Adams (mdawaffe)

Unfiltered MU gives Administrators and Editors the <code>unfiltered_html</code> capability. This prevents WordPress MU/WordPress 3.0 multisite from stripping <code><iframe></code>, <code><embed></code>, etc. from these users’ posts. Authors and Contributors do not get this capability for security reasons.
The plugin can either be used globally for your entire MU site, or it can be applied on a blog-by-blog basis.
For WordPress MU or WordPress 3.0 multisite only. Regular WordPress already offers this feature and does not need this plugin.
Warning! This is a very dangerous plugin to activate if you have untrusted users on your site. Any user could add Javascript code to steal the login cookies of any visitor who runs a blog on the same site. The rogue user can then inpersonate any of those users and wreak havoc. If all you want is to display videos on your WordPress MU blogs, use the native <a href="https://codex.wordpress.org/Embeds" rel="nofollow ugc">Embed Support</a>, <a href="https://wordpress.org/extend/plugins/vipers-video-quicktags/" rel="ugc">Viper’s Video Quicktags</a> or any of the other <a href="https://wordpress.org/extend/plugins/tags/video" rel="ugc">video plugins</a> on WordPress.org. 
If you use this plugin your site will be hacked in one way or another if you allow anonymous users on the Internet to create blogs on your site. It’s very dangerous.
Are you still 100% sure you want to use this plugin?

Unfiltered MU

I love when plugins are so cleanly written and do their trick without hassle. Especially after 8 years of no updates. Though they should submit an update just to remove the "2 years old" warning...

Still works! March 2017

This WordPress MU/WordPress 3.0 multisite plugin gives blog Administrators and Editors the ability to post whatever HTML they want.

User Object Framework vs Unfiltered MU