Netmon 3 - Nmcap.exe
Network monitor 3.0 has a command line tool as well to capture traffic. You can use the ‘Nmcap.exe’ tool to capture frames without the GUI. This tool is available in the Network Monitor 3 installation directory.
I'm looking for a way now to intercept the traffic on real time - like breakpoints on fiddler
more info can be found here: http://blogs.technet.com/netmon/