Currently run a small local area network for our small consulting company.  Three primary servers: one for file sharing only (NAS), one running Windows Small Business Server 2003, and the third server acting as secondary DNS running Windows 2000 Server.  

Domain-based network with local Exchange (on SBS 2003).  About 15 XP clients.  We do a lot of telecommuting and remote access.  Host FTP site locally.  Website hosted elsewhere.

I am self-taught, not a computer expert by nature (learning as I go).  Been running the network for about 5 years.