Got an opinion about firewalls or a question on cryptography? Join a discussion group. Here's a list of public and private mailing list services and Usenet newsgroups to get you started:
Security Newsgroups
Phreaking and hacking - Worldwide (alt.2600)
Hacker - Discussions
Phreaking and hacking - U.K. news
General security news
Pretty Good Protection® - Newsgroup
Java - Security issues
TCP/IP - Security issues
Computing risks
Computer security announcements
Internet firewalls
Misc computer security
Unix® security
Virus news
Misc security news