As part of my studies, I learnt about creating a game console pcb, and coding the embedded processor within it. This one is based on the AVR ATMEGA16 microprocessor.
Ultimately, it was put to use as an etch a sketch program. But the pcb leaves extra traces for the UART and I2C port.
Game console pcb
The schematic used for the board can be seen here as a pdf. pdf of the schematic
Altium Project files and C source code can be found in here