I manage a 1500 user/1000 machine network for a small school district in Ohio. My bag 'o tricks has the following items in it:
ARD-Remote management, reporting, and help
Munki-Package/app/software update deployment
Apple Software Update Server- OS updating (the munki client on the machine handles the actual updating of the machines as well as updating software like MS Office)
Workgroup Manager (moving to Apple's Profile Manager in the summer as WGM is thought to be going away)- Manages user accounts and MCX settings (MCX, if you don't know, is Mac's version of Group Policy however I find it a bit more flexible... it basically manages any .plist file either per user or per computer.)
DeployStudio-Imaging
Google- Generally with enough Google-foo you can find anything!
Mac administration is very hard work, mostly because not many people are as sadistic as we are, but it's very satisfying work!