When Kevin Rodgers embarked on his career in finance, dealing rooms were seething with clamoring traders and gesticulating salesmen. Nearly three decades later, the feverish bustle has gone and the loudest noise you're likely to hear is the gentle tapping of keyboards. Here is a very personal, often wryly amusing chronicle of this silent revolution that takes us from the days of phone calls, hand signals and alpha males to a world of microwave communications,...