SubSeven Trojan

I get scanned 20 or more times a day from people looking for pc’s infected with the SubSeven Trojan. My firewall always catches the scans, and stops them at the door. But is there anything besides closing the door to stop these people? I always look at the ip, and it’s normally pc’s with a cable connection doing the scans. There has to be a way to “spank” them. Reporting them to their respective isp’s is time consuming, and is most of the time a wasted effort. Anyone have any thoughts on this?