Used on http://drupal.org, "This module stores the changes of a node into a field attached to comments allowing to display a kind-of activity stream on the node much like on drupal.org issues just with a lot less custom code."

The gist: "This module extends the functionality of the core 'file' field, adding new capabilities to the file upload widget, and providing a new extendible field formatter for displaying lists of files."

Lets you use tokens to embed video and have the ability to add a button to the WYSIWYG for easily adding a video (for those to0 lazy to type).

"This module performs additional validation when a node is created or updated by a user to require that a node's title, author, language, and CCK fields are unique within a given context." There are many different contexts including content type. So, for example, you could make sure that nodes of a certain content type have unique titles.

Insert is the easy, secure way to let editors add images and links to files using WYSIWYG editors.

Flag is the ultimate bookmark tool. A must learn module.

An example module which integrates the Flag module with a custom form.

Gives replacement tokens. This module is used by so many other modules, you are sure to use it and learn it if you haven't already.

"This module provides an auto-increment (serial) field."

Not really needed most of the time unless you find that you want to be able to have a prettier way of providing values for multi-value key|value lists.

"Options Element is a module that provides a better mechanism to specify select list, checkbox, and radio button options. Rather than requiring the user to use strange syntax like "key|value" in a textarea, Options Element provides a clean interface for specifying options. Developers may