This looks a lot like Haml: <a href="http://haml.hamptoncatlin.com/" rel="nofollow">http://haml.hamptoncatlin.com/</a><p>Haml also happens to have a tutorial, documentation, and downloadable source code.<p>If you want to try Haml online, check <a href="http://lab.hamptoncatlin.com/" rel="nofollow">http://lab.hamptoncatlin.com/</a>