Most of the most up to date information is found on discussion groups in Usenet news. But sometimes I just don't have the time to wade through the various newsgroups just to find the information that I need. One thing I have found that helps me are mailing lists. Mailing lists are like discussion groups on e-mail. I use MS Outlook when I am in Windows and Kmail when I am in Linux.
Some mailing lists have the option of having the list sent in digest form.
This is real nice because you don't have to receive dozens of e-mails a day from that list. Below are a list of lists that I consider to be some of the most valuable to me for me to try and keep up with what is going on in the world of computer security. Computer Incident Advisory Capability Originally designed for the Department of Energy, this list has some good general purpose alerts. A mailing list discussion on the topic of firewalls and related issues. Network Security Assessment Network security assessment and security audit topics are covered here.