This is a board game helper device, originally designed to replace dual-dice used in Monopoly (because someone kept rolling them off the table or 'demolishing' houses and hotels on properties...).
For randomness, this has been created using the Entropy library for Arduino. In addition to the standard 2D6 needed for monopoly, this has a 1D6, and brightness control. We found we needed a random timer for auctions in monopoly, and later, a 30 second timer for the game Articulate!. Other times include 15, 45, and 60 seconds.
The device contains a piezo buzzer which buzzes to signal the end of a countdown, and in all but the random time beeps the last 3 seconds.
It also has a charge/boost board for the LiPo battery (600mAh) and can be charged from USB, estimated lifetime is about 6 hours for average use at full brightness (plenty of time for a decent game session).