An extensive, customisable, fully featured user tracking plugin.

MattGeri

Watchtower

Uptime and performance auditing, monitoring and alerting for WordPress.

digmedia

The DM User Tracking plugin is a fully featured, page by page tracking plugin for your blog. Every time a page is visited on your blog, the plugin logs a whole host of information on the person who visited the page.
The plugin is totally customisable from what you decide to track to what you decide you want to see. There is an optional dashboard widget included for a quick overview of recent visitors as well as a search feature for you to accurately sift through your tracking log and find the results you are looking for.
Data that is tracked by default:
<ul>
<li>IP address (including an attempt to locate IP addresses from behind a proxy)</li>
<li>The HTTP referrer (what page the user was viewing before they clicked)</li>
<li>The time of the click</li>
<li>User ID</li>
<li>User Level (admin, editor, so on)</li>
<li>Display Name</li>
<li>Browser</li>
<li>Operating System</li>
<li>The page they visited</li>
</ul>
Data that is not tracked by default but can be enabled:
<ul>
<li>GET variables</li>
<li>POST variables</li>
<li>Cookies</li>
</ul>
Please be sure to read the “Other Notes” section to view your responsibilities 
in using this plugin.
<h3>Your Responsibility</h3>
Upon installing this plugin you need to realise that you are potentially logging 
a lot of sensitive information on your users. You accept that by installing this 
plugin you are accepting not to misuse or abuse this data in any way. I will not 
take responsibility of any case of misuse of data caused by this plugin. That is 
the sole responsibility of the person who installed the plugin..This plugin is currently incompatible with the multi user function of wordpress we are working on updating the plugin to support the multiuser functionality.
.This plugin does not currently support blocking of ip addresses.

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