Due to missing IPX in Vista/2K8, its was not possible to play with your friends on LAN. But I've discovered an UDP patch for C&C games, that use IPX. IPX is replaced with UDP protocol, and the multiplayer runs a bit faster, too.

Tiberain Dawn, Red Alert 1:
http://www.understorm.net/cnc/lan/cnc95_ra1.php

Tiberian Sun, Red Alert 2, Yuris Revenge:
http://www.understorm.net/cnc/lan/ts_ra2.php


Enjoy!

FYI, for other games there is a software [commercial sadly, but I bought it!] called TCPCom that allows any game that can use "Null Modem" to work on a TCP-IP network! Of course, you can only play 1vs1 but it works flawlessly!

Also, do a google for the Hi-Resolution patch for C&C Gold - Tiberium Dawn [the original Command and Conquer] at 1024x768 is awesome!