contacting a x0vncserver without a NAT port forward, UPnP, etc.

[psilospiral]

I use x0tigervncserver on a Debian machine regularly when connected to the same LAN.  This machine is behind a router without port forwarding, UPnP, etc.

I want to access this machine from my home network, but have no way to forward the ports to the machine.

Is there a way I can setup x0vncserver to 'reach out' to my home IP address regularly to open the connection attempt from reverse?  Or would a relay or some other method allow this type of connection method?

I want to stay away from non-free, non-open source solutions like logmein or teamviewer.

[DRC]

In VNC, what you're describing is called a "reverse connection". The
idea is that you start a VNC viewer in "listen mode" on your client
machine, so it will listen for reverse connections from VNC servers. 
Then you start a VNC server on some remote machine and use a separate
program ('vncconfig -connect' with RealVNC derivatives like TigerVNC or
'vncconnect' with TightVNC derivatives) to instruct the VNC server to
create a reverse connection to the VNC viewer.  As far as I'm aware, you
have to use the TigerVNC X.org module in order to do that with Display
:0.  I don't think x0vncserver supports reverse connections.