Did you know you can customize the look and features of the clock that appears in the upper right corner of the menu bar? Just go to System Preferences, Date & Time and choose the Clock tab. You can display the clock as digital or analog. In digital mode, you can choose to show a 24-hour clock, show AM and PM, show the day of the week and display the seconds as well as the hour and minute. You can even have the colon in the time flash every second. You can also set up a chime to announce every hour, half-hour or quarter-hour.