My mother did used to embarrass me when I was a teenager, mainly by fussing over me in public. Once, at a high school basketball game where I was sitting with my friends and she was off sitting with other parent-types, she really succeeded. She came running up to me at half-time, grabbed my elbow, and shouted (in front of my friends) "Where's your purse? You lost it, didn't you? (I had a bit of a reputation for being absent-minded) I shouted back, just as loudly, "I didn't even bring it! It's at home!" She didn't believe me and continued shrieking; took me about five minutes to convince her that I considered the purse excess baggage and really hadn't bothered to bring it.

Now, I'm mainly embarrassed by my father-in-law, the old coot. He strikes up conversations with everyone: waitresses, salespeople, etc. But they're not friendly conversations, they're interrogations. He hits them with rapid-fire questions, never waiting for the answer to one before he asks the next, until they retreat in terror and confusion.