Okay, I'll bite on this one. Thank you for posting, Gellenburg.
I've had to go through hoops to get information to a customer and had to run around/through the IT department blocking my email. We had a time crunch, and it wasn't that sensitive of information, but policies were preventing me from sending, and we couldn't wait for IT to change rights to permit me to send this data. Sending ZIP files, for instance, was unpacked and scanned and blocked if the contents were funny. I used an unexpected archive format (my own).
I can easily see where you could detect the file names or database footprint of, say, a payroll database file. How good would your system be at finding the same data exported to spreadsheet format first?
Without compromising your system, what have you detected, and what couldn't you detect?