said by MartyT:If you are successful in getting your FreePBX generated files into a router based Asterisk system, let us know. I'm not a hardcoder like Mazilo on Asterisk, and would love to simply transfer FreePBX stuff over, but I'm not sure it works that way, at least it didn't when I tried it.
It would be nice to see some kind of AJAX based FreePBX interface for Asterisk when it runs on such a small system, unless someone has succeeded in getting FreePBX to run off the USB drive on a system like this on the WL-520GU.
Don't hold your breath... 
I'm very interested in programming and getting things like this work, but I wasn't interested enough at that important 'career choice' time (college) and haven't been able to invest the time since. 
The other limiting factor for me at this point is that I have to be wary of taking our gateway (the ASUS router) down when my wife's home. 
I may just have to hook up the old TrendNET while I play.