Like I said last week, I tend to drink coffee in cycles, and I have since I was at the newspaper. (Or at least, I used to have that cycle.) First I have a little in the morning - from the cafeteria here, a 12 oz. cup; from the kitchen in Vermont, one coffee cup - for a few days, then a morning comes along when I have a lot to get done or when I was up late the night before and I have a little more - here, a 16 oz. cup; back at my old job, two cups. After I get acclimated to having a medium cup in the morning, another day comes along when I need extra and I have a large cup. Then, eventually, I have a soda or iced coffee in the afternoon.
And then, by Saturday afternoon or Sunday, I'll have a dull, constant headache. I think this is because I got used to a certain amount of caffeine and then I haven't had any yet for a day or two, because I rarely have any on the weekends. This makes me realize I need to cut back to one small cup in the mornings.