Here's how I use Internet Sharing:
1. Install ActiveSync 4.5 on the PC that you want to share your connection with.
2. Start Internet Sharing on your phone. It should automaticaly connect to your dialup and display a message along the lines of, "check USB connection."
3. Connect your phone to your PC. Windows should create a new network connection and ActiveSync should not connect. If ActiveSync does connect, right click its tray icon, click Connection Settings, and disable USB connections.
4. Change your web browser of choice so that it connects through proxy wap.mycricket.com:8080.
This is VERY handy.