nmzmail is a tool to use the namazu search engine from within the mutt mail client to search mail stored in maildir folders. Based on the result of the namazu query, nmzmail generates a maildir folder containing symbolic links to the mails matching the query. A simple mutt macro makes easy to use nmzmail from within mutt. nmzmail is pretty similar to mairix, but the code is much simpler, as it uses an external program as search engine.
nmzmail is also available as FreeBSD port.
A mercurial repository can be found here.