[Techtalk] USB wireless as an AP?

[Elwing]

Chix,

I haven't ever tried using a USB wireless device under Linux, but I'm  
looking to create a separate wireless network off of my firewall  
(Debian w/IPtables), and "overcome" some of the rather poor design  
decisions of my current AP (Belkin).

What I'm not sure of is if I can even find a good 802.11g (n whatever)  
USB wireless device that works under Linux, will I be able to  
configure the firewall to act as an AP?

Features I need:
- WPA2 shared key (not an absolute necessity, but *very* nice to have)
- MAC address filtering
- hidden ESSID
- various wireless devices, computers, laptops, and "devices" will  
need to connect to it, so funky limitations on what it'll talk to  
won't work for me.

Any experiences with either 1) a USB wireless device or 2) using Linux  
as a wireless AP?

Thanks!
Elwing