July 2009: I move in with J who is a regular coffee drinker, so it's always around.
Last spring / early summer: I read several articles about how caffeine consumption shortly before exercise improves performance, which makes sense when you think about it. I decide to try it out but only on longer runs. I add a cup of coffee to my breakfast on the days I'm going to the trail to run (going to the trail equals a run of at least five miles.) I'm not sure if it helps as I can't run a double blind study on myself, but it certainly doesn't hurt.
Last fall: I started taking a college class, which meant I was up earlier than J on school days as well as running days. Borrowing an idea from a friend I start to make coffee on those mornings so it would be ready when he got up, but still only drank it if I was running longish.
Late November/December: show from hell. Not enough sleep or sanity. I started drinking coffee on the weekends to gear up for a long day, and occasionally before class too. Also, as the weather got colder I realized I like having a warm drink in the morning.
Now: I have a cup of coffee daily, sometimes more. On short run days I have my coffee after I get back (before I just have some gatorade and get out the door). According to J this was his secret plan all along.
So I've become a coffee drinker. I don't drink it black, I prefer my coffee with a generous portion of milk (1%), though I suppose I may fall off that slope someday too.