Ruwa is a open source web analytics made in Rails. Ruwa features:

• Draggable Widgets and jQuery support
• Visitors, Referrers and Search engines reports
• Database agnostic: you decide to have MySQL or Postgresql
• Programmable Widgets and custom reports
• Cannoli: track clicks and generate click heatmap

Check out the blog to know more.

You can download the latest release from:

http://github.com/rosario/ruwa