I was in my boss' office complaining about a coworker. The coworker came in and we talked about this issue sort of like, "Oh, since you're here..."
The next day, that coworker came into my office and said that overnight he began to realize that I had been complaining about him to my boss. He was very mad and asked me not to do that in the future. I was so embarrassed.
When I was much younger and living from paycheck to paycheck, I had a great boss who always made sure I took food home from corporate luncheons and so on. She looked after me as best she could and I appreciated it so much. I was telling her about a woman I had seen in a store and how I knew she was an older woman because the skin on the back of her hands had begun to get sort of papery.
My boss just looked at me. Not picking up on the cue, I looked at her hands and said, "Just like that."