A mini macro keyboard using Arduino Micro. You can assign all kinds of functions to it, such as open a software, type a greek simble, unlock the computer, etc.
For people with no experience of Arduino, a brife tutorial of how to assemble and program the Arduino, as well as an example Arduino file are included.

Things you will need:
Soldering iron and some wire
1 Arduino Micro
6 mechanical keyboard switches
6 keycaps