This paper presents a library for Arduino to interface with the DS3231, a high-precision I2C real time clock (RTC) with an integrated temperature-compensated crystal oscillator (TCXO) and crystal. The ...
You can buy all kinds of conventional clocks that have hands and numbers for easy reading. Or, like [Fabio Ricci], you could build yourself something a little more esoteric, like this neat shadow ...
Currently your Arduino can only beep like a microwave oven. Mozzi brings your Arduino to life by allowing it to produce much more complex and interesting growls, sweeps and chorusing atmospherics.