A few stand out.
I love my parents, but this fall they both participated in a fantasy football league. My Dad in particular felt the need to give me weekly updates on who Mom was playing, and who he was playing, and how their respective team's outlooks were, etc. I thought it would be obvious to him after a while that I really didn't care, because all I'd ever say was 'that's nice, Dad,' but apparently it never sunk in because I got those updates right through to the final week.
My grandma has a habit of always telling me about her friends, none of whom I know. She goes into great detail. Over Christmas she told me that 'Eloise is in rehab,' and I replied 'drugs, or alcohol?' and I think that must've offended her. Renegade points! But any conversation with her ends up being some detailed reports on which of her UPenn classmates will be coming to the reunion in July, or some letter she got from someone she knew 50 years ago. It wouldn't be so bad except that she can talk about these people for hours on end, and there's no escape.