Useful 3rd-Party Modules in Moodle 2.0

MOODLE (Modular Object-Oriented Dynamic Learning Environment) is the world leading learning management system (LMS) running on PHP architecture. Being modular enables Moodle users to contribute into creating many additional features that can be plugged-in the system.

The Moodle Community contributes numerous modules or plugins in many form such as blocks, activities, resources, reports and hacks. I found the following third-party modules are useful and available for Moodle version 2.0:

• Activity Module  
•  Book - makes it easy to create multi-page resources with a book-like format.
• Certificate - generates PDF certificates for students upon meeting specified course criteria. (patch for v2.0)
• Feedback - survey your students with custom questions and scales which is now a part of standard distribution in Moodle 2.0
• Block
• Configurable Reports - examine custom course and user reports and custom MySQL queries.
• Login & Logout - promotes social networking features in Moodle by providing users with a time-based greeting calculated using the server's time and the user's timezone, user profile image, last login data and profile update link. (update for v2.0 by András Gazdag)

Do you have a favorite third-party module that is not listed here?