> I personally know at least 5 exploitable vulnerabilities in some government websites, but I won't be disclosing them, since that will land me in a lot of trouble.
Thats what full disclosure is for. Drop the vuln somewhere via Tor, maybe point someone there via some anonymous comunique. Et voila, you made the world a safer and better place.
Imho sitting on vulnerabilities is immoral as long as anonymous full disclosure is possible.