Windows XP Pro has a feature called internet connection sharing, which will allow you use the other NIC as a router. Plug your Linux box into your WinXP box with a crossover cable, or hook them both up to a switch in case you don't have a crossover cable or want to connect more than one machine to your WinXP box's other NIC. You can enable ICS (Internet Connection Sharing) on the WinXP as a service on the Network Properties Page for the interface you want to use, I think. I have only set it up behind a Windows 98 machine, but there are Help documents available when you go to Start > Help > Search > and then type in internet connection sharing. A router would be useful, but it can be expensive and a crossover cable is $5.