Just for your convince i have compiled a best resources, these are scripts, hacks, JQuery Plugins, WordPress Plugins, a list of Websites providing web stats  included in this article. If you know any other, mention it in comment.

1. Google Analytics Extensive Tracking Analysis of Websites

I believe most of us are using Google Analytics in order to track our visitors daily. With This excellent Tool you can track and compare all your ads, email newsletters, affiliate campaigns, referrals, paid links, and keywords on Google and other search engines. Use Google Analytics to learn which online marketing initiatives are cost effective and see how visitors actually interact with your site. Make informed site design improvements, drive targeted traffic, and increase your conversions and profits.
Search Engine Journal has compilied a list of advanced Google Analytics tips that open up plenty of possibilities to track and evaluate.

2. Google Analytics API is Now Available to Developers

A Google Analytics API has long been one of our most widely anticipated features. Developers can integrate Google Analytics into their existing products and create standalone applications. For example, Polaris is a cross-platform desktop widget for Google Analytics. With 8 standard reports it’s the easiest way keep your data always instantly available. The rich interface and swift navigation make it a pleasure to use.

3. Yahoo! Web Analytics – Highly Customizable & Powerful

Yahoo! Web Analytics is a highly customizable, enterprise-level website analytics system designed to help website businesses increase sales and visitor satisfaction, reduce marketing costs and gain new insight on online customers. By storing data in raw, non-aggregated form, Yahoo! Web Analytics is more than simply a reporting tool. It is a powerful, and highly flexible, data analysis tool. Both near real-time AND historical data can be segmented instantly and even visualized with advanced graphs to help marketers and site designers answer specific business questions and find new insights to improve their business.

4. How to Create a “Who is Online” Widget

A well explained and very good Tutorial written by TutorialZine on “Who is online” widget with PHP, MySQL and jQuery. This widget display the number of visitors, their country and display it in a slide out panel.

Demo | Download

5. Apigee Provides Analytics, Protection and Control for APIs

Understand customers, usage patterns and app behavior with detailed analytics and alerts on API traffic, clients, errors, and data volumes. I provide Free up to 10,000 Messages per hour.

6. Open Source Web Analytics Framework in PHP

The Open Web Analytics (OWA) framework provides a generic set of PHP and HTTP APIs that application developers can use to integrate web analytics into any application. The Framework also has built-in support for popular web applications such as WordPress and MediaWiki.

7. GoingUp – Combines Web Analytics with SEO Tools

GoingUp’s web stats features a fully customizable desktop with easy-to-read graphs and data charts. See visitors, referring URLs and even search engine traffic! Show only the data you want to see with slick AJAX interface! Set custom tracking events to see sales, downloads and subscribes!

8. Get a Full Featured Pingdom Account for Free

Pingdom is a service that monitors websites and servers from the Internet and alerts you if there is a problem. It acts like a watchdog, making sure that your website is up and running 24/7. You handle all your settings from an online control panel. No need to install anything. You can get error alerts via both email and SMS.

9. Odometer Style Javascript Counter in Mootools

UvumiTools Odometer is an odometer style Javascript counter, where you can actually see the numbers spining. It is a Mootools plugin requires no Flash, it’s all CSS and Javascript.

10. Crowd Science

Crowd Science Demographics is a new audience measurement service that gives website publishers insight into the demographics and attitudes of their audience. Focusing on more than page views, clicks and behavior, Crowd Science Demographics builds an audience profile including age, gender, income level and other demos that provide you insight to your audience.

11. Compare Traffic with Google Trends for Websites

With Google Trends for Websites, you can get insights into the traffic and geographic visitation patterns of your favorite websites. You can compare data for up to five websites and view related sites and top searches for each one.

12. Comparing FeedBurner Subscriber Numbers

A free web application that you can use for comparing FeedBurner feeds. This tool is great for checking out your competition and noticing trends in growth.

13. W3Counter – Hosted Realtime Website Analytics Solution

Demo

14. Woopra Realtime Web Tracking & Analytics Tool

Woopra is the world’s most comprehensive, information rich, easy to use, real-time Web tracking and analysis application. We deliver the richest library of visitor statistics in the industry through our innovative desktop application. But Woopra is more than simply statistics.

15. Piwik – Open Source Web Analytics

Piwik is a downloadable, open source (GPL licensed) web analytics software program. It provides you with detailed real time reports on your website visitors: the search engines and keywords they used, the language they speak, your popular pages… and so much more

Demo

16. Track, Monitor and Analysis Your Flash (SWF) with Mochibot

MochiBot give Flash developers an easy and effective way to track their Flash movies. Other tools in the market are either not made to track Flash content, too expensive, or just too hard to use.

Demo

17. Free Web Counter for Your Website from SiteMeter

Site Meter is a comprehensive real time website tracking and counter tools give you instant access to vital information and data about your sites audience.

Demo

18. Snoop Tracks Your Visitors and Events On Your Desktop

Reinvigorate measures your influence on the web in real-time. Gain up-to-the-minute insight into your audience, then adapt to meet their needs and watch your site grow.

Demo

19. StatCounter is Another Free Reliable Web Tracker

A free yet reliable invisible web tracker, highly configurable hit counter and real-time detailed web stats. Insert a simple piece of our code on your web page or blog and you will be able to analyse and monitor all the visitors to your website in real-time!

20. SlimStat – Open Source Extensive Analytics Program

SlimStat is an extensible web site analytics program. Its interface is an exercise in simplicity. Visits, referrers, browsers versions, platforms and searches can all be taken in at a glance.

WordPress Stat Plugins

1. WassUp

This is the statistic plugin that I am currently using. It gives you real-time statistics which is the part that I really like.

2. WP-Stats

This is another great WordPress plugin for finding out your statistics. This may be the most popular one among WordPress users. But don’t think that means it is the best.

3. WordPress Blog Stats

This helps you integrate the W3Counter service into your self hosted blog.

4. Official StatCounter Plugin

If you use the great service StatCounter for getting your blogs statistics, then you will likely love this plugin. This allows you to use their service in your admin area. This means that you will not have to go to their web site to get statistics.

5. CyStats

This is another great statistic plugin that I also use. It shows you a little more information about your statistics. A lot of times I like as much information as I possibly can get.

6. StatPress Reloaded

This was made to keep the Statpress plugin alive. The original creator does not keep the original updated anymore so this was created. Also one of the most popular plugins to get your statistics.

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