possible tutorials - if you need ideas
1) Tutorial explaining the basics of firewalls and the difference between packet filtering, application, and circuit firewalls. Also maybe something about hardware vs. software based.
2) Basics of routing/routers/routing protocols - what they are, what they do, how they work.
3) Crypto - basic terms, examples of some different types, explanations of how they basically work.
4) Basics of any programming language you may know....links to other resources for people to learn more.
5) How to build your own tools for monitoring your computers/network with the language of your choice.
6) Explain how to secure the operating system of your choice.
7) Explain some of the ways you make your code harder to break (do you have good routines for preventing buffer overflows, input checking, etc). Always nice to learn how to write better code.
8) Explain how to secure the web server of your choice.
9) Explain the protocol of your choice - how it works, known problems, possible weaknesses.
10) Explain the most common mistakes made by system administrators and how not to make them.
11) Explain the legal issues related to monitoring/tracking hacking activity on your network/computer. I'd love to see something about this.....I've read some interesting things about hacking being legal/illegal in some countries and what could be done to solve the problem. Also about how logs/files from the compromised computers were used in court and the issues related to each. Anyone have any real life experience with this?
These are just general suggestions....not for you specifically. If I can think up anything more I'll post it.