I've been following this nstx
tutorial. I set up a server on tunnel.nix.is. It's set
up
to use the tun1 interface there. See also this tutorial for iodine.
Since the server is also a shadow DNS master for several domains I compiled a custom nstxd that listens on port 5252/udf instead of 53/udp. So these are the listening processes:
$ sudo netstat -ldnp | grep :5[23]