"Since Google Analytics was launched in 2005 it has become one of the top analytics packages for small to medium sized websites. Growth was initially slow due to the frustrating waiting list system initiated by Google to avoid over stretching their servers. Now that the waiting list has been removed anybody can sign up to use this great service."

Excellent tutorials on customizing, extending and simply making the most of Google Analytics.  

via BlogStorm: Advanced use of Google Analytics Part I and Part II