Event Organiser allows you to create and maintain events, including complex reoccurring patterns, venue management (with Google maps), calendars and customisable event lists.
Shiny Buttons will help you to generate CSS3 Button from you WordPress admin simply using a GUI.
Simple Google Adsense lets you simply add Google Adsense to your blog.
WP Marketplace is packed with all necessary features you must need to build a e-shop for your single product or a full featured complete market place.
Akismet filters out your comment and track-back spam for you, so you can focus on more important things.
FoxyPress is a custom plugin made to integrate FoxyCart e-commerce functionality into your WordPress website.
Joemobi allows you to create native Android and BlackBerry applications from your WordPress site.
PollDaddy allows you to create stunning surveys, polls, and quizzes in minutes.
Traffic Analyzer can be used to determine the number of visits to each post or page available in the site.