Story time: Shortly after I was hired at SiemensVDO, my group leader came by just to say "Hi" and looking at him with my "concentrated" face I asked in a husky voice "What do you want?". Totally caught him by surprise, so he barely mumbled "I only wanted to say Hi" and walked away. The floor was open office, with at least 50 people in the room. He was known as a very severe manager, which demanded a lot from the programmers (also he was a former Uni teacher hired by Siemens 10 years earlier), and whenever he was entering our big room, everybody rushed to look busy and kept their head down, not wanting to be caught in his gaze.
Funny thing about the situation is that I was unaware it was him when I said that, and only after he left I fully understood what just happened. In any case, he was severe but also a just manager and recognized hard workers. After that little incident he treated me differently than any other person in that floor. When talking with me he started using a "sweet" voice, reserved only for his bosses while continuing to use his "rough" voice with everybody else. I became "de facto" person to tell him unpleasant stuff for that room, and funny enough this led to an even better relation between us. One of the best managers I had in my 10 years tenure throughout different corporations before I became freelancer.