I felt very caffeinated today. For me, the line between "fairly awake" and "very caffeine-stimulated" mostly appears to be a function of when I'm drinking it rather than a function of coffee volume consumed. Late afternoon seems like the time when caffeine is most effective (or maybe a little too effective, depending upon the level of focus the day requires). A few recent papers and at least one science blogger explain this effect in terms of cortisol levels and the circadian rhythm. See also: the concept of the zeitgeber.

I'm also reducing the level of anonymity for this blog, as you may have already noticed. This trend will continue. The person writing this is the same person who does everything else that person does every day.