Gource project link: <a href="http://code.google.com/p/gource/" rel="nofollow">http://code.google.com/p/gource/</a><p>Previous discussion on gource and DHH's rails commits visualization: <a href="http://news.ycombinator.com/item?id=1329495" rel="nofollow">http://news.ycombinator.com/item?id=1329495</a>