Over the past five years or so, my wife has consistently been disappointed with my utter inability to explain what I do at work in a short, pithy way that works at parties. I could just say "I'm a Sysadmin", but I'm not just a tape monkey, or a Windows re-installer, so I try to avoid the short title, because people have in the past assumed I don't do anything truly productive.
My job at this point is Systems Architect, but no one outside of Systems departments knows what Systems Architects do, so that doesn't help much on the party circuit.
When I've tried to explain more fully what I do, I have fallen back on metaphors of building trades. Basic sysadmin stuff (setting up accounts, changing backup tapes, etc.) is like being a building super. Setting up new servers is like contractors putting up buildings (or more floors on an exisiting building). Debugging and troubleshooting are like electricians and plumbers fixing problems. Designing large-scale installations is like being an architect (which is why we're Systems Architects, duhhh).
This may explain why I usually feel pretty comfortable with people that build and maintain stuff -- cognitively, we're all pretty similar.
White collar professions, too, are subject to routinization and degradation, proceeding by the same process as befell manual fabrication a hundred years ago: the cognitive elements of the job are appropriated from professionals, instantiated in a system or process, and then handed back to a new class of workers — clerks — who replace the professionals.
One of the reasons I do what I do is that I find it challenging -- as much as they might want to replace us Systems folk with clerks, they simply can't. Here's hoping it actually stays that way.