Instructables member Dennis Cwik has published details about his "Cwik Clock" - a fascinating mix of a binary and analogue-meter display clock powered by the Arduino platform. Although binary clocks aren't anything new, Dennis' version is finished nicely and has a sensible user interface. Furthermore, the seconds are displayed using the analogue panel meter on the top, for example:
Another great project with purpose and a great result. To get started with your own version, check out Dennis' instructions here.
Although some clock designs rely on internal timing in software, for accuracy and reliability include an accurate real-time clock IC. Here at Freetronics we have the Maxim DS3232 real-time clock IC module:
Apart from keeping accurate time for years due to the temperature-controlled oscillator and having a tiny coin-cell for backup, it is very simple to connect to your Arduino project. A driver library allows your program to easily set or read the time and date. Perfect for clock projects, dataloggers or anything that needs to know the date and time. Furthermore it contains a digital thermometer and 236 bytes of non-volatile memory to store user settings and other data. For more information, check out the module page here.