Can I run an AppleScript upon my 3G modem connecting? I'm looking for a way to run an AppleScript after my 3G modem is successfully connected to the carrier.

The modem is using the standard OSX network panel to connect, so it's not using any crappy carrier software.

Around the web I've found a lot of people running stuff after the modem is connected but it seems to be sending AT command to the modem, and I don't want that. I want to launch an AppleScript on my computer.
Try ControlPlane. It lets you trigger various events, including launching scripts, based on various system events, including what networks you're connected to. I'm not 100% sure if it will read any network interfaces, or just the default ones, but it's free and probably worth a look.