I have a sun box the IP 192.168.1.100 which is connected to a HUB. A W2K box which picks up its IP address (68.x.x.x) from Cable provider which is also connected to the HUB. Cable Modem connected to the Uplink port on the HUB. How do make it so I can connect to the sun box from the W2K box while still being able to surf through the Cable Modem? Or is this even possible?

What you are trying to do is impossible. You need either a second NIC in the W2K box or a router. If you opt for the router you plug the modem into the router which then picks up youe ISPs IP address. Then through Network Address Translation connects to the two computer via the hub. If you opt for the second NIC, you can connect the two computer together through one with an IP address in the range 192.168.0.x for each, and the Modem through the other. I am not sure if WIN2K does Internet Connection Sharing or if the SUN box will share an internet connection through the W2K box. But if they will you need to set up Internet Connection Sharing on the Win2K box. The router is the most robust and relieble solution, but more expensive Stuart

Install a router on your network. Most of them have a built-in basic firewall for network protection. Then set your w2k box with an address 192.168.1.x

A router would ONLY be required if you also wanted the Sun box to cruise the internet at the same time the W2K wkst which from what you describe is does not do now. If you were to make the Sun box's ip address in the 68.x.x.x range and NOT conflict with the W2K box's ip address you should be able to network between the two stations while the W2K box is also on the internet. No additional hardware required.