Markus had a spare MSP430 microcontroller have decided to make simple alarm clock of it. He used a four digit 7 segment LED display controlled via 74HC164 shift registers.
He connected two push buttons for interactions. And finally he added a buzzer to play alarm tunes. He made it really miniature and power efficient. It draws about 10µA in standby mode. So set and forget for about 10 years.