This is just out of curiosity, I don't have any need for this kind of 
functionality, it's more of a how hard would that be kind of question.  
With talk of PIX firewalls earlier on the list I was thinking about how 
much we paid for a pair of PIX 515s.  The second firewall we bought cost 
us next to nothing, because it would function only as a failover device 
in case the primary failed (it would refuse to load it's config if the 
master wasn't present).

I was just curios as to how hard it would be to implement something 
similar in m0n0wall, and if anyone had ever inquired about it before?