Coca-Cola was born in an era of tonics, restoratives, and bottled pick-me-uppers, and it was advertised as a cure for, among other things, "slowness of thought". Caffeine, we now know, can bring with it, in sufficient quantity, restlessness, nervousness, excitement, insomnia, flushed face, . . . periods of inexhaustibility, psychomotor agitation, and several other of the well-known conditions of our accelerated times.
— James Gleick, Faster