I walked out of my building at the end of the work day and noticed a couple of guys coming out of an alley, I recognized one of them as someone I used to work for. I said "hi" and got a pretty strange look in return. Then he says "Hi, Terry??" in a puzzled tone. Once he realized it was me he said "boy, do you ever look good. Have you lost weight?". I told him I had, he asked how. I told him diet, weight training and cardio everyday.
It really made me feel good that someone noticed and decided to say something!