The OneKeyBoard is just that - a keyboard that has only one key. Plug it in to your PC and it will recognize itself as a keyboard. Open any text editor and hold it for 5 seconds, and it will output simple instructions on how to program it through tapping to any key, key combination, or shortcut you wish.
Why is this cool? Think about the possibilities for use:
PCB Only option contains ONLY the circuit board
Assembled options comes with Gateron Blue Switch - switch LED may be added, USB mini cable not included