Originally posted by Sixpax
It's a tad more difficult, but does give you better control if you put the script in /etc/rc.d/init.d and make a link under one of the run level directories (/etc/rc?.d). This allows you to not only have it start at boot time, but lets you stop it and restart it at will as well as making sure it DOES get stopped (if that's necessary) when you reboot/halt your system. With some programs, just letting the system kill the process can cause a hassle.
That's not really necessary with the DNS2Go package; your system and their server exchange a "heartbeat" handshake every second or so, and when you don't respond, their server switches your status. When this happens, the client package in my machine tries every 15 minutes or so to reconnect (if it's running, of course). Thus operation is entirely automatic.
I launch the client package in rc.local and it works quite well. I don't like to modify the "standard" scripts unless absolutely necessary, mostly because I would lose all my mods on an upgrade...