I'll never forget the time some friends and I were in a heated discussion about CRT's. Those of us who were engineers were referring to "Cathode Ray Tubes" (one of several technologies for TV or PC monitor displays). We couldn't figure out how our friend, who was in the laundry business, could be so into the conversation. Turns out HE was talking about "Cabinet Roller Towels" ... those cloth towels on a continuous roll you find in restrooms (at least over here in the US!) It's amazing how well the conversation went despite the disconnect. We were talking about "viewing angles" and there he was, "Yep, yep - 'ya gotta be right in front of 'em for things to work right!"