Lot of plugin available for  stopping the spam but mostly used and best blugin given here. THese plugin will help to improve the comments sections and stop the spam comments. It is true that most trafic, most comments and most spam. Most of plugin have Captcha that control useless comments.Some plugin contain facility to count the comments and prevent the duplicate comments.Study the list of top 30 plugin

1.WP Grins Lite

WP Grins Lite will provide clickable smilies for both the post form in the admin interface and the comments form of your blog. WP Grins Lite uses the lighter footprint of the jQuery library.

2.WP Ajax Edit Comments

The most powerful comment editing solution for WordPress. Users can edit their own comments for a limited time, while admins can edit all comments.

  • Can edit, de-link, move, mark for moderation, mark as spam, and delete a comment from a post.
  • Can edit in all comment panels in the WordPress admin panel.
  • Can de-spam, approve, moderate, and edit comments in the Akismet panel.
  • Various admin-panel options including

3.CommentLuv

This plugin will visit the site of the comment author while they type their comment and retrieve a selection of their last blog posts, tweets or digg submissions which they can choose one from to include at the bottom of their comment when they click submit.

It has been found to increase comments and the community spirit for the thousands of blogs that have installed it. With a simple install you will immediately start to find new and interesting blog posts, tweets and diggs from your own blog and community.

4.Kaskus Emoticons

Kaskus Emoticons is emoticons used in kaskus forum. Kaskus it self is the largest Indonesian community that has millions members and posts. Some images here are copyrighted by Kaskus.

5.SI Captcha Anti Spam

Adds CAPTCHA anti-spam methods to WordPress on the comment form, registration form, login, or all. In order to post comments or register, users will have to type in the phrase shown on the image. This prevents spam from automated bots. Adds security. Works great with Akismet. Also is fully WPMU and BuddyPress compatible.

6.Invisible Defender

This plugin protects registration, login and comment forms from spambots by adding two extra fields hidden by CSS.

7.yaCaptcha

yaCAPTCHA is a CAPTCHA plugin for WordPress that helps you block comment spam from automated bots. In order to post comments, users will have to write down the characters that are part of an image. Since it is relatively hard for automated programs to figure out those characters, this will help prevent comment spam from those programs.

8.WP Comment Auto Responder

This plugin will send a automatic mail message when you visitor leave a comment on your wordpress blog.

Other feature of this plugin is when you or other visitor reply your visitor comment from your dashboard this plugin will make automatic message, and will tell to your visitor that their comment has replied.

9.GeoSmart

GeoSmart automatically adds city-precise location information for each comment author to comment metadata for each comment and a map showing comment author location distribution. GeoSmart also ships with a multiple instance capable sidebar widget that displays a map showing the locations of the most recent visitors to your blog.To display these maps you will need to obtain a Google Maps API Key

10.Thank Me Later

Thank Me Later (TML) will automatically send an e-mail to your those who leave a comment at your blog. Use this plugin to say ‘Thanks’ to your visitors, and prompt them to further engage with your blog.

TML is highly configurable. It allows you to create multiple e-mail messages and to send the message after a pre-defined amount of time, making messages appear more unique and people-friendly.

11.Kau-Boy’s Comment Notification

This plugin enables blog admins and editors to manage the notification of incomming comments. As WordPress only has the option to notify on every comment, the email account of the admin may recieve many email each day. Notification is also limited to the admin only, so only the admin user will recieve an email for incomming comments.

Using the plugin you can subscribe to a RSS feed that contains even comments that has to be moderated.

12.DISQUS Comment System

Disqus, pronounced “discuss”, is a service and tool for web comments and discussions. The Disqus comment system can be plugged into any website, blog, or application. Disqus makes commenting easier and more interactive, while connecting websites and commenters across a thriving discussion community.

13.Commentwitter

Commentwitter is a WordPress plugin that gives commenters the option of Tweeting their comment with a link to your post.

Other features

  • Automatically creates bit.ly to specific comments in a post
  • Integrates nicely into forms
  • Blog owner can Tweet new comments automatically on their profile

14.Quote Comments

This plugin adds a tiny link that says “Quote” on each comment on your posts. Click it, and the contents of the comment is copied to the comment area, wrapped in blockquote tags.

15.Vertical Scroll Recent Comments

This will vertically scroll the recent comments in site side bar or any desired location with avatar or name or none.

Feature

  • It’s scrolling vertical so we can display more comments
  • User can see the newest comments at sidebar.
  • You can customize the number of recent comments to display.
  • It’s scrolling so it occupies less space in sidebar.

16.Advanced User Agent Displayer

the Advanced User Agent Displayer plugin displays the Browser and the operating system of people who commnet on your blog. Currently Support for Desktop and moblie operationg systems and browsers. Browsers: Internet Explorer, Opera, Firefox, Safari, Chrome, Epiphany, Avant, Maxthon, Konqueror and … Platform: Windows(2000, XP, Vista, 7), Linux, Mac, iPhone.

17.TinyMCEComments

This plugin turns the comment field from a primitive <textfield> into a WYSIWYG editor, using the internal TinyMCE library.

18.Comment Form Quicktags

This plugin inserts quicktags of the admin page to the upper part of textarea of the comment form.

Features

  • You can edit tags in the admin page.
  • You can limit quicktags by user roles.

19.@ Reply

This plugin allows you to add Twitter-like @reply links to comments. When clicked, those links insert the author name and a link to the comment you are replying to in the textarea.

20.Liz Comment Counter by Ozh

Liz Strauss Comment Counter is a highly configurable badge (very similar to the Feedburner one, except it’s more configurable) to show off the number of comments your blog has.

21.Digress.it

Digress.it lets you comment paragraph by paragraph in the margins of a text.Embed paragaphs YouTube-style on other sites.

22.Greg’s Comment Length Limiter

This plugin provides a configurable limit on the length of comments left in the comment form, with a character countdown displayed for the user and dynamically updated with each keypress.

23.WDP AJAX Comments

This plugin will integrate AJAX commenting feature into your WordPress Blog. It uses the powerful JavaScript Framework jQuery to handle AJAX requests and jQuery Validation plugin by bassitance.de to validate comment form on the client side.

Feature Summary

  • Enable AJAX Commenting
  • Client Side Form Validation
  • Easily rolls back if JS disabled
  • Easily configure custom styles for messages

24.AVrAmTAR

AVrAmTAR.com is service which allows user to register and upload multiple avatars in their account. After that user will get his unique URL to the dynamic GIF image which will show different avatar (chosen from avatars user have uploaded) each time URL is accessed.

25.Wp-AuthorComment

Allows you to uniquely style post author’s comments.

26.Get Author’s Comments

This plugin allows to display or retrieve comments posted by a user. In order to avoid homonyms, a user is identified by his name and email(s).

27.Cookies for Comments

This plugin adds a stylesheet to your blog’s html source code. When a browser loads that stylesheet a cookie is dropped. If that user then leaves a comment the cookie is checked. If it doesn’t exist the comment is marked as spam.Copy into your plugins folder and activate. If you are using a caching plugin such as WP Super Cache make sure you clear the cache after enabling this plugin.

28.BackType Connect

The BackType Connect WordPress plugin finds conversations related to your content and allows you to display the associated comments inline with your own. Existing conversations about your content taking place across the web can now be displayed right on your blog for your visitors to read and respond to. It works on top of your existing WordPress comments, both threaded and non-threaded.

  • Twitter – tweets that link your posts
  • FriendFeed – on the entries for your posts
  • Digg – on the submissions for your posts
  • Reddit – on the submissions for your posts
  • Hacker News – on the submissions for your posts
  • Other blogs – whenever someone links one of your posts

29.WP-Reply Notify

If you answer comments, you can get information through the blog address of comments. The other way, you can see information about comments other blogs send by admin e-mail.

30.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!

Horizontal Position

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