What do I (the engineer) do?

Many times I need to explain, to non-technical people, what it is exactly I do. I'm sure many engineers have run into this issue before, and end up explaining how the entire universe works before they finally end up with "... and I design the X that goes in Y..." Well, it can be even more baffling when your area is modeling and simulation, where the work contributes to something physical, but isn't a terribly tangible thing. It occurred to me that I can draw upon some of the more recent phenomena of the merging of social networking and games, such as interactive worlds (e.g. secondlife, the Sims, etc). Thus, what I do, day in and day out, is create virtual worlds (modeled transistors/circuits/semiconductor devices) for electrons. The simulator is just the platform that pushes the little electron "people" around. See, its that easy!