The first after I saw the usage "an FAQ" and realised that while I pronounce it "Fack" in my head other people pronounce it "Eff Ae Queue". The second because the correct usage of smileys within brackets has long plagued my mind.
Andy: Is typing Julie: Is watching TV. A trailer for something dramatic and chick-flicky comes on. Julie: "Nooooooo! I can't believe they made a movie of that!" Andy: "What is it?" Julie: "One Day. We have a copy of it in the flat. It's awful. We use it to squash spiders."