Jesper has an interesting post describing some of the pros and cons of using CrazyEgg to generate heat maps (a color coded map of where the clicks are happening) on your site.

Results depend on how users use the mouse. Results will be skewed by users that don’t use mouse, users that use a laptop with trackpad or another device for moving the cursor around on screen.

I haven’t had a chance to play with CrazyEgg yet so I can’t chime in with my opinion yet. Most of the sites I actually own contain a lot of Javascript links, so I’m not sure if CrazyEgg can track those clicks or not. Maybe I’ll test it out on this site.