1) Family Heritage. I don't care about your family heritage, and who married whom over 100 years ago and how close their old house is. Hubby's crazy-ass sister is obsessed with it. She will talk for HOURS about her family genealogy, which no one, not ever her own family, gives a flying fuck about.
2). Cell phones. I don't care what your phone can do; I barely care what mine can do. Get your damn phone out of my face and when we're together, look at me and not your phone, thank you.
3). Religion. No, I haven't found Jesus. I'm not religious. I'm an atheist. Please don't tell me that I'm going to hell, or that my soul is lost, or try to get me to join your Church, or I might be tempted to tell you what I think about your particular superstition, in great detail. I keep my mouth shut so as not to offend you; please do me that same courtesy.
4) Your crazy-ass conspiracy theories about this group or that ethnicity, or that politician or WHATEVER it is you don't like, and how it's ruining everything,
is to blame for everything
in the entire world would be better without it. You're just making yourself out to be an incredible idiot, not to mention being really hateful/bigoted/paranoid, and no one wants to hear it. Stop drinking the Kool-Aid and try to have a civil conversation.
5). Sports. Don't care. No interest. Please be quiet.