Dear h4x0r. Please don't bother scanning my network for FTP, ident, RPC, NFS, foo, bar or baz. I don't run them. You're wasting your bandwidth and mine. You're wasting your time and mine. And you're messing up my pretty logfiles where I hope to see a list of packets which I accidentally blocked with the firewall.
On days when I am sufficiently bored, I will whois the IP and call the ISP, especially if someone else is paying the phone bill. ISPs tend to be very sympathetic and very accomodating and I get a kick out of getting accounts terminated.