ESP8266 powered LED Matrix clock
Download the code here: https://github.com/Legorobotdude/esp8266-LED-matrix-clock
The circuit consists of an ESP8266 as the brains and wifi connectivity, a 3v-5v logic level shifter in order to interface with the 5V led matrix, and the matrix itself. Additional debug circuitry in the picture includes a USB Serial Converter, and an Arduino Micro to supply power.