After being inspired by a similar project, Instructables member stregoi decided to recreate their own verison (and at a lower cost) of a large Domino Clock. This type of clock uses three huge dominos, each of which represent a digit in the current time.
The dots for the numbers are usually commerically-available flip-dots, however due to the cost the creator has made their own versions complete with small home-made electromagnets. This has been a success and quite easy to replicate if you have the time, and the final example is pleasing to the eye, for example:
Controllin the dots is simple with high-power shift register ICs which is explained along with construction and sketch details on the clock's Instructable page. And for more, we're on facebook, twitter and Google+, so follow us for news and product updates as well.
The most important part of any clock project is the inclusion of 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.