Couple of great open source resources for Heat Mapping and click path tracking. Find out where people are clicking and how long they’re staying.
Also if you have a complex site and are looking to track paths of your visitors to find out where they’re leaving you can check out.
It has the capability of adding plug-in’s to it that will allow you to track conversion. It’s written in PHP and easily extendable to suit your needs. A great place to start if you want to create a full fledged tracking system for and E-commerce site or a large scale site with paths to a sale.