vlc dshow:// :dshow-vdev="CompUSA PC Camera" :dshow-adev="none" :no-dshow-config :dshow-size="320x240" :sout=#transcode{vcodec=DIV3,vb=128,scale=1}:duplicate{dst=std{access=file,mux=asf,url="c:\temp\my_output_file_name.asf"}}
Replace "CompUSA PC Camera by whatever your camera is seen by in VLC (do an Open Capture Device, Refresh next to the Video Device area, look at the choices that are available)
vb=128 sets the output nominal bitrate
You can also add:
--sout-transcode fps # where "#" is a real number, to set the frame rate.
For instance, maybe the camera is able to output 30 fps, but you're happy with 5 -- setting the smaller number lets you use a lower bitrate for a given quality of output
http://videolan.org/doc/misc/VLC%20Streaming.pdf might be the doc you wanted, though there's a brand-new streaming guide on the docs page, too.