Outbound ports to firewall?

[Parker Morse]

-----BEGIN PGP SIGNED MESSAGE-----
Hash: SHA1

Like most people, I've put some effort into filtering incoming email 
and firewalling my network to prevent nasties from getting in. But 
recent discussion of preventing the spread of Windows worms, viruses, 
etc. etc. has led me to a question I don't have an answer for.

Let's assume, for a thought experiment, that one of the Windows boxen 
inside my gateway firewall is infected with *something*, who knows 
what. To protect the rest of the 'net from this little bundle of 
pestilence in the time before I track it down and choke it to death, I 
should probably have some firewall rules to keep the bulk of the 
nastiness from leaving my network. Outbound rules.

What ports should I consider closing up to keep hypothetical infected 
inside my network from phoning home and/or spreading the infection?

Thanks,

pjm
-----BEGIN PGP SIGNATURE-----
Version: GnuPG v1.2.4 (Darwin)

iD8DBQFBVCE4nRVGoRROKxIRAlY6AJwNfaqDNjqkUXf/q9qP+XKfM4hcwwCdHGMs
ewSWmlTgQ3uCEu6WfxNazpQ=
=NEYK
-----END PGP SIGNATURE-----