Expensive yet stable
www.realnetworks.com
free basic trial server and 30 day large server software trials
after playing with the free trial client, we paid the $199.95 plus tax for the client to get linux and "other" feature support with it.
Haven't played with the linux side of the client much yet because I do not think the capture card supports linux.
there are other options
chris posted about the mac video software platform recently when I started a similar thread as you.
I haven't been able to get to it yet
- rh