I have an idea, it may be stupid, but if someone of us hosts a little little server redirecting to yours... i think there will be at least someone on.
I've just done it... look in the action room.
ps
Are you sure that it isn't a port forwarding problem??? I'm sure you just know that the ports to forward be added to the list are:
26900
27900 (Master Server UDP Heartbeat)
28900 (Master Server List Request)
29900 (GP Connection Manager)
29901 (GP Search Manager)