Start an Ad Hoc Network
Click the "Start" menu and type "Network and Sharing Center" in the search box at the bottom of the Start menu.
Select "Setup up a connection or network" and select "ad hoc" as the network type to continue setup.
Enter the necessary configuration info for your network. Enter a name of your choosing in the "Network name" dialog box and select the "Security type," if any, you want to use on the network. You may choose from WPA and WEP encryption types. Finally, enter the security key for the network in the "Security key/Passphrase" box.
Click "Next" and then "Close" to finalize configuring the ad hoc network to share your 3G USB modem between two PCs.
Read more: How to Connect Two PCs With a 3G USB Modem | eHow.com http://www.ehow.com/how_683500...g-usb-modem.html#ixzz209jYwjHe