I’ve never read the column regularly, but I heard about a case in which a female real estate agent wrote him to ask if it would be ethical for her to stop doing business with an Orthodox Jew, because he wouldn’t shake her hand (which to her uneducated mind showed that he thought women were inferior or polluted or something). Mr. Ethics said yes, certainly! I understand that even after many Orthodox rabbis contacted him to explain the real reasons, he never retracted his answer.
I think there was an article on Torah Musings in the last few months about one of the Ethicist columns.