Basic Idea

I recently bought a new AVM Fritz!Box for mine and my parents internet DSL dial-up connections. This became necessary because our provider decided - rather unexpected - to enable ADSL2+ (wikipedia-link) on our line. Since our modem is a first generation DSL-modem this would no longer work. As we noticed afterwards - we had not been noticed of this before. This was about 6 month ago. Now Fritz!Boxes do offer some kind of VPN functionality - but only as a VPN-Server, not as a client. Since I am connecting my systems through a VPN-Server I run on a Hetzner Root Server. So what I need is:

1. the ability to connect the network at my parents - and sometimes my - place to my private VPN.
2. the ability to run a customized firewall including a DMZ
3. the ability to have fixed IP-addresse for certain hosts configured into my DHCP-Server
4. log into my Fritz!Box through an SSH-connection for administration
5. and somewhat more two wishlist items:
   1. have IPv6 in combination with my sixxs.net account and
   2. use port knocking

Solution

Use Freetz - as it seems. I have not yet tried it, but I will in the near future. A problem seems to be the SSL-Libraries in the current (1.1) release. Something strange in combination with original Fritz! SSL-libraries (see ticket 491: http://www.freetz.org/ticket/491)
Übersetzung kommt noch - so lange bitte die englische Seite anschauen.