Each organization in a company has their Favorite Application. It's not truly their favorite application; it's just the application they must use in their particular capacity in the organization. Stand up right now and walk into an unfamiliar part of your building and stalk your coworkers. If someone stops and asks you what you're doing, tell them, "Rands sent me," and vigorously nod your head. That always works.
As you walk the hallways of this strange new part of your organization, look at their screens. What's the consistent application sitting on their monitors? Is it Excel? Well, you're probably in some area of operations. Are you seeing a lot of Word? Maybe legal, possibly tech pubs. Is the cube empty? That's ...