Today Olimex posted first pictures and early specs for their 5x5cm small SBC computer.
SPECS
5x5cm PCB (1.9x1.9inches)
H3 quad core Cortex-A7 processor
512MB of DDR3 RAM
2x USB hosts for mouse and keyboard
Ethernet 100Mb interface
HDMI Full HD output
4 buttons
micro SD card
UART console
USB-OTG which also is used to power the board
4 mount holes
2x 40 pin connectors (optional) which carry lot of GPIOs
OS
Android
Linux
So ideal for Linux / Android trackers or for VJing as it can do 4K video! And yes you will be able put it into your pocket with your Gameboy!