1. Category Order
The Order Categories plugin allows you to easily reorder your categories the way you want via drag and drop.(compatible with 3.4.2) http://wordpress.org/extend/plugins/order-categories/
2. WordPress Reset
Resets the WordPress database back to it’s defaults. Deletes all customizations and content. Does not modify files only resets the database. http://wordpress.org/extend/plugins/wordpress-reset/
3. External Links
Force all external links to open in a new window. Add rel=nofollow to all external links. Add an icon to all external links. http://wordpress.org/extend/plugins/sem-external-links/
Project management and task tracking software… think Basecamp for the WordPress Dashboard!
5. Snazzy Archives
Snazzy Archives is a visualization plugin for your WordPress site featuring an unique way to display all your posts. Your archive page will never be boring again! http://wordpress.org/extend/plugins/snazzy-archives/
6. WP Smush.it
Reduce image file sizes and improve performance using the Smush.it. Every image you add to a page or post will be automatically run through Smush.it behind the scenes. You don’t have to do anything different.You can also run your existing images through Smush.it via the WordPress Media Library. http://wordpress.org/extend/plugins/wp-smushit/
7. WP Greet Box
Display a different greeting message to your visitor depending on which site they are coming from.
8. WordPress Download Monitor
Plugin with interface for uploading and managing download files, inserting download links in posts, and monitoring download hits. http://wordpress.org/extend/plugins/download-monitor/
9. Google XML Sitemaps for Videos
The Video Sitemap plugin will generate an XML Sitemap for your WordPress blog using all YouTube videos that you may have embedded in your blog posts. http://wordpress.org/extend/plugins/xml-sitemaps-for-videos/
10. nRelate Related Content
nRelate is designed to drive eyeballs deeper into your site by displaying related content as either thumbnails, text, or both. http://wordpress.org/extend/plugins/nrelate-related-content/
11. SEO Smart Links
Lets WordPress automatically link keywords and phrases in your posts and comments with corresponding posts, pages, categories and tags on your site. http://wordpress.org/extend/plugins/seo-automatic-links
12. Viper’s Video Quicktags
Allows easy and XHTML valid posting of videos from various websites such as YouTube, DailyMotion, Vimeo, and more. http://wordpress.org/extend/plugins/vipers-video-quicktags/
13. Tweet Old Post
Plugin to tweet about your old posts to get more hits for them and keep them alive.
14. upPrev Previous Post Animated Notification
When a reader scrolls to the bottom of a single post, a button animates in the page’s bottom right corner, allowing the reader to select the next available post in the single post’s category.
15. SEO Rank Report
Track your Google rankings every 3 days and see reports of your progress in a graph. You will also be able to visualize your traffic flow in response to ranking changes and receive emails notifying you of major rank changes.
16. Social Media Tabs
Social media tabs allows you to add facebook, google +1, twitter, flickr, pinterest, YouTube subscription and RSS profiles and feeds to any widget. http://wordpress.org/extend/plugins/social-media-tabs/
17. Pricing Table
WordPress Pricing Table plugin will help you to generate pricing table in the easiest and dynamic way.
18. Lightbox Plus
Lightbox Plus permits users to view larger versions of images, simple slide shows, videos and content all in an overlay. http://wordpress.org/extend/plugins/lightbox-plus/
19. Booking Calendar
Its a plugin for online reservation and availability checking service for your site.
20. Widget Logic
Widget Logic lets you control on which pages widgets appear using WP’s conditional tags. It also adds a ‘widget_content’ filter. http://wordpress.org/extend/plugins/widget-logic/
21. Theme My Login
Changes your normal WP login page to another page on your site that you can configure yourself.
22. Visitor Maps and Who’s Online
Displays Visitor Maps with location pins, city, and country. Includes a Who’s Online Sidebar. Has an admin dashboard to view visitor details. http://wordpress.org/extend/plugins/visitor-maps/
The best Post Ratings plugins online, and it’s free. Adds an AJAX rating system for your WordPress blog’s post/page. http://wordpress.org/extend/plugins/wp-postratings/
24. Sidebar Login
Easily add an ajax-enhanced login widget to your site’s sidebar.
25. PHP Code Widget
Like the Text widget, but also allows working PHP code to be inserted.