Security

One of the things I seldom talk about, both due to my Disclaimer and to my ingrained dislike of the "it's got to have a half-dozen firewalls to be secure" school of thought.

Resources:

These will be mostly non-obvious or intriguing ones - there are far too many people posting links to bugtraq and suchlike, although Schneier is mandatory reading if you actually want to use your brain to deal with security...