1. Paypal Donate Widgets
This is a simple plugin for wordpress widgets that let your user can make paypal donation via your blog site.
2. WP Snap Preview
This is simple snap preview anywhere, less option but full.
3. WP Amazon context link ads
Amazon Context Links are a quick and convenient way to add links to blog and help you monetize your content. Context Links automatically identify and link relevant phrases within your blog content to Amazon products.
4. WP Flickr Widgets
Get your flickr photo shown on your blog’s sidebar.
5. WPMU Share This
This is Share This modified version for wordpress MU base on Alex’s excellent plugin. Just download and upload to your wordpress MU mu-plugins folder. No plugin activate request.
This plugin allows you to easily present a list of posts you select outside of your blog chronology. Very useful for featuring things that might otherwise slip into the nether regions of your archives.
6. WP Odeo Plugin
Embbed Odeo Audio on your blog content.
7. Doogate Search Widgets
Adds a sidebar widgets to let users search your site with Doogate.com
8. WordPress Meebo Widgets
Embed meebo widgets on wordpress sidebar.
9. WP Bookmarking Widgets
WP Bookmarking Widgets is allowing people to subscribe to your blog via services such as Google Reader, Bloglines and MyYahoo! and more.
10. WPMU Comment Timeout
Reduce your comment spam with comment timeout. This plugin automatically disables comments on older blog entries after a certain period of time. It also gives you an option to automatically keep them open for longer wherever there is an ongoing discussion. This WPMU Edition is modified by Patrick Chia based on James McKay Comment Timeout.
11. WPMU Latex Math
This is modified based Anders Dahnielson mimeTex. It’s allowed blogger to include inline Latex formulas in blog posts and comment. It’s use wordpress.com format to embed the code, example: $latex your-latex-code-here$
12. WPMU Random Blog Redirect
Allows you to create a link to yourblog.example.com/?random which will redirect someone to a random blog, in a StumbleUpon-like fashion. This is modified based on Matt Random Redirect.
13. WPMU Random Captcha
Stop a lot of spambots from polluting your site by making visitors identify some random text displayed as an image before signup blog. The latest version add captcha image on signup and login page.
14. Theme Extras: Snow Effect
Add snow background effect to your blog for coming Christmas. (Please see this blog) This plugin is make your blog like winter. So you no need to change your blog theme.
15. WordPress and WordPressMU Standard XML Sitemap
Add standard XML sitemap into your wordpress blog and robots.txt automatically.
16. Multiple Twitter Widgets (Latest: WordPress Plugin Directory)
The widgets allows for multiple twitter widgets to be displayed.
for WordPressMU and WordPress Personal
17. Dashboard-Myblog Widgets
Showing user’s blog on the right now with dashboard and settings link. This plugin for WordPress MU only and version 2.7.
18. WPMU-Admin-Languages (Latest: WordPress Plugin Directory)
Simple plugin that allowed user to set up different language in Admin Panel and blog interface.
19. Gravatar Favicon
This plugin allows you to generate a gravatar favicon for your blog and admin logo included Apple touch icon. Just activate the plugin, and it will add gravatars to your blog template and admin panel automatically, no setting and nothing.