Build a fully functional binary clock with your Uno
If you want to show everyone your computer prowess—or perhaps get a little practice—binary clocks are a great way to do so. These clocks express time in 1s and 0s instead of 0 through 9, and while the concept is pretty simple, actually creating one is less than straightforward… or used to be.
The Binary Clock Shield, now on Crowd Supply, aims to make this type of clock build extremely easy. This board plugs into an Arduino Uno and features 17 RGB LEDs to act as binary digits, along with an RTC module and backup battery socket.
The device also includes a piezo speaker for sound output, plus three user buttons, great for setting the time or whatever other unique application you have in mind!
[original story: Arduino Blog]