1. Have your computer hooked up to the internet by means of a modem.
2. Plug in the ethernet calbe from the Xbox 360 into your computer via either an NIC or your motherboard.
3. Enable Windows Media Connect, and set your firewall accordingly
4. Click start, connect to, and then click show all connections.
5. Find your dial up connection, and right click it, then click properties.
6. Click the Internet Connection Sharing checkbox
Hope this helps for some folks!!