A clerk who helped me purchase a small digital voice recorder told me that he kept one just like it in his car when he worked in California. “When I began driving home after work I switched it on,” he said, “and I talked about everything that happened that day on the job, good and bad. When I pulled into my driveway, I hit the erase button.” Then he smiled. After telling everything to his voice recorder, he apparently had no need to go over the day’s problems with his wife or family.