USB Ethernet or Wireless Adapter?

[John Brayton]

I wonder if someone could give me some guidance on a problem I have run 
into.

I am moving a personal server to a home network with one public IP 
address.    The server runs on a bondi iMac running Yellow Dog Linux.  
The hardware has one ethernet port, and no slot for an Airport card.

I am currently using an Airport Base Station for NAT, as well as 
wireless access throughout the home.  But the Airport Base Station only 
allows port mapping for ten ports, and I need more ports than that open 
on the server.

I think I have three options:
-Replace the airport base station with a router that can provide port 
mapping for more than ten ports.
-Add a USB ethernet adapter to the server, and use it as both a router 
and a server.  Connect the airport base station via Ethernet to the 
server, for wireless clients.
-Add a USB wireless adapter to the server, and use it both as a router 
and a server.

My question is:  Are there any USB ethernet or USB wireless (802.11b) 
adapters with drivers that work with Yellow Dog Linux?  I am assuming I 
can use natd to do the IP sharing, although I have no experience with 
this.  Are there any pitfalls I should be aware of?  Would I be better 
off getting a new router?

Any advice would be appreciated.

John