Web mail server, build with node.js, python, redis, solr and backbone.js. Development is stopped at the moment.
Initial motivation was to build a "nicer", custom web mail UI with smart email processing. This goal was achieved: Curie reached a level of maturity where I could use it as my main web-mail. The email processing flow works fine and it allowed new problem to surface — spam. And that's there Gmail shines, so after a month or two of using Curie every day, I switched back to Gmail.
Please see the documentation at http://traut.github.io/curie/