Plugins

BlockUI Plugin (Updated 20-MAR-2009): Simulate synchronous ajax by blocking - not locking - the UI.
Cycle Plugin (Updated 17-MAR-2009): Image or text slideshows with numerous transition options.
Feeds Plugin: Wraps the jQuery syntax around the Google AJAX Feed API.
Form Plugin (Updated 08-APR-2009): All kinds of information about the Form Plugin including a quick start guide, code samples, API documentation, a FAQ and more.
HoverPulse Plugin (Updated 26-FEB-2009): Pulse an image on mouse hover.
Media Plugin (Updated 26-MAR-2009): One plugin for handling your Flash, Quicktime, Windows Media Player, Real Player, MP3, Silverlight, PDF and more.
Round Corners plugin (Updated 26-FEB-2009): Rounded corners without images. Plus lots of other corner adornments.
Taconite Plugin (Updated 24-JAN-2009): A port of Taconite to jQuery. Make multiple DOM manipulations in response to a single remote call.

Demos

Ajax Events Demo (Added 26-OCT-2008): Demonstrates how jQuery's global ajax events work.
Custom Expressions: Demo page which shows how you can extend jQuery's ':' expressions with your own favorites.