The Arduino are hobbyist interface boards which can be programmed to perform endless things; with enough creativity you can implement the boards into your project quite effortlessly.

The advantage of the Arduino boards —

1. Affordable – the Arduino Mega 2560 board can be purchased at under AUD $20.00 and will not break the bank.
2. The Ardruino Mega 2560 Rev 3 board has 54 digital input/outputs, they can be programmed to your project requirements.
3. Outputs operate at 5 volts so they are fully compatible with Airbus korry switches.
4. MobiFlight software allows you to interface the Arduino boards with Flight Simulator X/Prepar3D using FSUIPC offsets.
5. Operational over a network using MobiFlight and WideFS.

I have been testing the Arduino Mega board the last few days and work very well. Unfortunately direct output wiring to an Airbus korry switch is still not possible because if the higher current requirements of the incandescent bulbs.  Using Darlington Transistors (ULN2003A) however the outputs work correctly, and logic can be controlled with MobiFlight.

Terr on ND Korry successfully lit up using the Arduino Mega 2560 Rev 3 board and a Darlington Transistor

Simon has more information on Darlington Transistors on his website.

Lighting up a Korry using Darlington Transistors; schematic courtesy of Simon Stusek