What I do is run an Agent on my "other" PC. I set the Agent up to use a "Local" device - in my case a Sony FireWire camera. Then, on the AbelCam server PC I just do "Add Agent" and enter the IP and port of the "other" PC. If all you want is the videostream this will work fine and you only need to get an Agent, not a second full AbelCam. But if your second cam has Pan/Tilt and you want to use it, then you need a second AbelCam.

Agent is basically AbelCam Lite. Costs less, does basic video capture and serving, but not the more advanced stuff like pan/tilt, motion detection, etc.

Check here: http://www.multicamserver.com/en/AbelAgents

And also here: http://www.multicamserver.com/en/AbelAgents/index_html/abelcamnetwork_html