Network problem

No.

No, but if one of your computers has 2 internet ports available (one wired and one wireless), you can hook that up to your modem using a LAN cable and share the internet connection wirelessly with the other computer. Of course, both must be wireless capable. If one or both is not, you can buy cheap USB adapters at any computer store.

Instructions on how to do this:

XP: http://support.microsoft.com/kb/306126

Vista: http://windowshelp.microsoft.com/Windows/en-US/Help/bfd...

Mac OS X 10.5: http://docs.info.apple.com/article.html?path=Mac/10.5/e...

Have you ever setup ICS (you can use wired connections as well)? It's a royal PIA.