Don’t get caught… this clock doesn’t have moving parts. HDD is only as case for a clock. Design is really neat and uses no fancy components like SMD or etched PCB. So everyone can make it on old HDD. LEDs on a HDD platter look really cool. In the dark it should give nice effects.

Binary clock is running on AT90S2313 as it can be replaced by ATtiny2313 now with no code modifications.  Circuit is really simple - matrix of LEDs is controlled by using transistor keys, and additionally there are three buttons for setting time. Source code is also available which is written for AVR-GCC compiler. To see live action of binary clock, view video of the clock.