I am a systems administrator at a small manufacturing company. I am slowly transitioning to the role of Knowledge and Information Manager so having a Wikipedia account seems to make sense.
I know about:
General Computer use, small business networking, Server 2003, Windows XP, some Mac, some Linux, VPN, wireless, wiki (we run Socialtext), ERP (we run JobBOSS), social networking, malware cleanup,
Several other things that I can't think of right now.