ISP Modem Dialup

Greetings list people.
The list has been very quiet recently but I have just started looking at 
my USR wlan and I am wondering if it could do the job of being a access 
point with a dial on demand interface to a isp using an external modem. 
Does anyone know if this is at all possible.? Waht I have in mind is 
something like an Apple airport with built in modem. Is there anybody 
there taht can help me? I have already got it converted to Linuxap V 
20030831.16:21:01 with terminal and web interfaces.
n.b. would it be a simple matter to include a file manager , does 
anybody know how to do this?
Regards,Dave.