(Heat map of the ethercycle.com navigation depicting clicks of 1,764 users during a 7-day period.)
While traditional analytics data can often feel like abstract statistics, heat maps are an easy way to understand user behavior. More importantly, they can diagnose confusing design elements by showing if users are clicking something they shouldn't.
We recommend Labs Media's ClickHeat. It is open source software, released under general public license, and free of charge.