I'm really amazed by SC version - this is exactly what I was looking for... Before I found it I even created a special overlay for VNC with Client and server - Client installing/launching VNC servers without use interaction and connecting to an admin from the list (predefined in client) - and Server/listener waiting for an information from a Client and after admin confirms, allowing VNC server->viewer connection.
And this is only thing I miss - not in SC itself, but in vncviewer - a feature allowing to "freeze" incoming connection from a SC (or standard UltraVNC), pop up a box saying that there is an incomming connection from an address w.x.y.z (or/and comp. name) and asking to approve or reject it.
I think it would be really useful feature to prevent heart-attacks when someone connects to your viewer all of a sudden

best regards
Maciek