Most useful WordPress Plugins Collection.

Twitter Widget Pro

A widget that properly handles twitter feeds, including @username, #hashtag, and link parsing. It supports displaying profiles images, and even lets you control whether to display the time and date of a tweet or how log ago it happened (about 5 hours ago, etc).

Twitter Friends Widget

Twitter Friends is a WordPress plugin that displays your Twitter friends/ followers in your sidebar in the same way that they appear on your Twitter homepage.

EasySMS

EasySMS is a great way for WordPress administrators to txt message their readers and broadcast a new post to users cell phones. Admins can group subscribers together for more productive SMS messaging. This plugin is great for organizations or churches to stay in touch with their employees, volunteers, or constituents.

Subscription Options Plugin

The most common ways for people to subscribe to a blog and its content are through RSS, Email and Twitter. This plugin places three matching icons in a widget area and lets users enter their own feed URLs.

WP Content Protector

Excellent Plugin To Protect Your Valuable Blog Content. This plug-in will disable right click on your blog and disable selection of text So that no one can simply copy and paste the content of your blog in there blog or site.

Transposh

Transposh translation filter for WordPress offers a unique approach to blog translation. It allows your blog to be translated by your readers in-context.

WP-SEO Boost

WP-SEO Boost Plugin is the best SEO solution for all your blog.WP-SEO Boost Plugin offers all the features of all SEO Plugins available plus few more advanced features added.

Zemanta

Zemanta provides contextual content recommendations to you while you write. It enhances your blog post with relevant images, videos, links, and SEO optimized tags. All recommended content is blogger friendly with clearly marked licenses (Creative Commons or similar).

Google Analytics Dashboard

Google Analytics Dashboard allows you to pull the Google Analytics profile data for your site into your dashboard as well as other parts of WordPress such as posts.

Google Analytics for WordPress

The Google Analytics for WordPress plugin automatically tracks and segments all outbound links from within posts, comment author links, links within comments, blogroll links and downloads. It also allows you to track AdSense clicks, add extra search engines, track image search queries and it will even work together with Urchin.

StatBadge

Statbadge displays up to 16 different statistic values about your blog. You can select each one of them to be shown or not. You can integrate Statbadge everywhere in your template or via the sidebar widget.

GravatarGrid

Displays the Gravatars of all your commenters as a nice mosaic in the sidebar of your blog. The plugin is widget ready and comes with many configuration options.

Last.fm For Artists

This plugin adds a sidebar-widget to list an artists upcoming shows or top tracks from Last.FM (using the new 2.0 REST API).

Series

Series is a plugin created to allow users to easily link posts together by using a WordPress taxonomy (e.g. tags, categories) called “series”. It can be particularly useful if you write several posts spanning the same topic and want them tied together in some way.

GD Star Rating

GD Star Rating plugin allows you to set up rating and review system for posts, pages and comments in your blog. You can set many options for displaying the rating stars, and also add widgets into the sidebars for displaying top ratings and other statistics generated by the plugin. Plugin includes advanced settings panels that will allow you to control many aspects of rating. Plugin also supports multi ratings.

WP Likes

WP Likes allows vistors to “like” your posts on the fly just like in FaceBook with cool transition effects. A good way to show-off the value of your post, as many people refrain from posting comments even though they find your content interesting.

Easy Popular Posts

An easy to use WordPress function to add popular posts to any theme. The results can be displayed in many ways and it has been tested with popular caching scripts.

WP Widget Cache

A high-performance caching plugin for WordPress, and a plus for WP-Cache or WP Super Cache./p>

Collapsing Pages

This is a very simple plugin that uses Javascript to form a collapsable set of links in the sidebar for the pages. Every page corresponding to a given parent page will be expanded.

Feed Reading Blogroll

The plugin improves your blogroll by displaying the freshness and the latest post-title of your bookmarks.

Sidebar Photoblog

Simple photoblog plugin. Sidebar Photo blog doesn?t use lots of server resources and doesn?t have any confusing options. It uses WordPress functions to get maximum compatibility and flexibility.

Lightbox Plus

Lightbox Plus is a plugin that implements Lightbox JS by Lokesh Dhakar. Lightbox Plus is used to create overlay display images on the webpage and to automatically add the correct overlay links to images. Lightbox Plus permits users to view larger versions of images without having to leave the current page, and is also able to display simple slideshows.

iRedlof Ajax Login

iRedlof Ajax Login adds a beautiful Javascript loaded Login/Register top panel to your wordpress theme.This plugin is based on my iRedlof Inspire Theme.

Pretty Link

Shrink, track and share any URL on the Internet from your WordPress website. You can now shorten links using your own domain name (as opposed to using tinyurl.com, bit.ly, or any other link shrinking service)! In addition to creating clean links, Pretty Link tracks each hit on your URL and provides a full, detailed report of where the hit came from, the browser, os and host. Pretty Link is a killer plugin for people who want to mask their affiliate links, track clicks from emails, their links on Twitter to come from their own domain, or generally increase the reach of their website by spreading these links on forums or comments on other blogs.

ICS Calendar

This plugin provides a graphical interface for adding and customizing the format of how calendar events are displayed on your site. It also includes a widget for displaying events in the sidebar. There is also an ajax calendar that you can place on your blog, which uses AJAX.

Floatbox Plus

Floatbox Plus is a plugin that implements Floatbox by Byron McGregor (a javascript similar to Lightview/Lightbox/Shadowbox/Fancybox/Thickbox). Floatbox Plus is used to create overlay display images/videos (only youtube/vimeo) on the webpage and to automatically add the correct overlay links to images. Floatbox Plus permits users to view larger versions of images/videos without having to leave the current page, and is also able to display simple slideshows. Floatbox Plus captures the image title for display in the overlay.

Actionable

Actionable allows the creation of a categroized list of action items for users to check off and track. It was originally developed for Share 350.0 – a plan for regional sustainability to help people track their actions and efforts to create a sustainable community.