I can't nail down the exact date, but I believe PowerDNS 2.0 shipped sometime around 2001-2002 with pipe backend support. It allowed you to craft dynamic responses to DNS queries from any language you could get to run on Linux.
Yeah this was my thought, too. I was using PowerDNS to do this sort of thing within a basic home environment. But I have no idea if it has the necessary features to keep a production environment happy. It was fun to play with.
