i think i have a copy of advanced server 2000 laying around here, not sure where i put it tho

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i'm not going to be actually using this machine as a firewall, i probably mislead a bit there. i just meant i was going to use good firewall software to protect the machine. it's not going to bridge connections or anything. i also plan on using several antivirus/spyware programs on the machine, to prevent theft or corruption of the data.
however, from what i remember of the pre-launch assemblies and stuff i went to on 2000 pro, yes, it can do the multiple network thing.
edit: forgot to add, xp pro also does the dual nic thing pretty nicely. in fact, it's pretty sweet with the whole wireless thing as well. had a deal for a while that a friend of mine was working at my place for a while, and had wireless on his laptop and a desktop. at the time i didn't have wireless, so we hooked up the desktop to the hub, and using it's wireless nic, made a gateway for the laptop. you can go into the network settings, and if you have 2 networks running, right click or something and click "bridge connections". works really slick.