Internet Connection Sharing is a way to share your internet connection for other computers. It requires two network cards on your computer. It also requires a crossover cable or a switch/hub between your network cards. You can use this if you have to pay for an internet connection. With ICS two or more people can connect while only paying for one. You can also use this to make a machine as a gateway for your office. However, complications arise if you are running a Windows Active Directory domain or already have a DHCP server. This feature is available on Microsoft Windows 2000, xp, vista, 7, server 2000, 2003, 2008. (less info)