Here’s a cool way to check which portions of your pages are being clicked by viewers. The author of this article has used Javascript to capture the mouse clicks on the screen and save the location to the database using Ajax.

“One of the more interesting aspects of Ajax is the ability to track a user’s interaction within the browser. I wanted to investigate navigation patterns, so I have written an Ajax based link tracker. If you press the “Ctrl” and “X” keys you will be presented with an overlay which displays links usage by percentage. This functionality was created with JavaScript and a very simple API.“

Link: Ajax Link Tracker