RDF

Neologism is a lightweight web-based vocabulary editor and publishing tool built with Drupal. It makes RDF vocabulary authoring easy and fun. Just create a vocabulary, add classes and properties to it, and your vocabulary is instantly published and available online! Several formats are supported via content negotiation: HTML, RDF/XML and Turtle.

About the current stable version

Get it from the main project website!

Provides an API for arbitrary node relationships based on RDF.

Friendlist is a foundation needed to build a social network-oriented website with Drupal 6.

At the very basic level, it provides the ability to create custom relationships between users. It's a feature-rich suite of modules that features integration plugins with a list of major Drupal modules (see below). Admins can create relationship types. Both single (think: a fan) and two-way relationships (e.g. a friend) are allowed.

Related Projects: Activity Log, HeartBeat

ATTENTION: If you enable Friendlist_Rules make sure that you use the latest DEV Snapshot releases of both Token and Rules modules (not: the stable ones) or the module won't work and will throw errors!

Documentation:

Just moved to new location, so under development: FriendList Docs

Features:

• Integration with Views
• Integration with Rules
• Integration with HeartBeat
• Integration with CCK Field Privacy
• Integration with Popups 1.3.x
• Integration with Node Access
• Buddylist and Buddylist2 migration assistant.
• User Relationships migration assistant.
• Configurable set of relationships. One-way relationships, two-way relationships with confirmation, two-way relationships without confirmation (using Rules)
• Working user interface, out of the box, with configurable system messages [using t() function]
• Complete user and developer documentation.
• Sample code snippets for people who want more low-level access than using Views.

Provides activity streams like those seen on Facebook, Yammer, and Google+ where users can keep track of recent, interesting activity on the site. It is designed to be easy to use, yet extremely flexible, extensible, and standards-compliant.

What are Topic Hubs?

Harnessing the power of Calais tagging, administrators can create Topic Hubs based on site’s most popular tags. Topic hubs are highly configurable and contain a series of pluggable content modules, like “Most Read” content for this topic, “Most Commented” stories, most active contributors, and links to other related topics. To top it off, integration with Calais Geo allows for plotting all of your content for a Topic Hub content on a map.

This module is no longer maintained. You can simply use rules to remove a role from a user, so she won't be able to post new content

Create quota module creates quota rules and holds information about every user's creation count.
A possible use case for this module is a site that allows users to register for free and to create a certain amount of content until they are asked to pay for the service.

Module is pluggable and allows other modules to implement their own quota rules.

Dependencies:

What does this module do?

Most PDF modules generate PDFs from scratch; FillPDF is not one of those modules. Instead, it lets you fill in existing editable PDFs with data from your Drupal site. Editable PDFs are those forms that let you type into them. Read more.

FeedAPI RDF processor saves feed item data in RDF format.

Requires RDF module and FeedAPI module.

This module automatically converts media files to different destination formats, and allows you to change a number of properties such as pixel size, frame rate, bitrate etc. It is designed as an extension of the FFmpeg Wrapper module. A common use for a module like this would be to convert video files to FLV or H264 in order to be able to embed them in a browser.

Marmoset's purpose is to provide a simple way to make your Web site's contents available through intelligent search.

This module integrates the Calais Marmoset site crawler into Drupal. It adds a tab on the node that when selected will display the microformat data returned my marmoset.
Click through for more information about Calais marmoset