s6 is unreleased software. It will be released at some point in 2011 or 2012, when the documentation is considered decent.
s6-dns is an alternative DNS suite. It obsoletes the skadns package.
s6-dns contains:
There are plans to also implement a caching resolver and various DNS servers, all supporting the DNSCurve protocol, at some point. However, it will likely be years before the author's schedule allows this to be made.