An Arduino is a popular open-source single-board microcontroller. Learn how to program one and let the possibilities take shape. By The Big Book Of Hacks Published Jan 10, 2013 3:00 AM EST Get the ...

To start, you need to buy an Arduino. It comes pre-assembled or, for those handy with a soldering iron, in kit form. A fully assembled Diecimila board from the excellent Make costs just $35.

You can read the state of a button using Arduino and a few lines of code. The actual state is shown in the Serial Monitor window as 0 or 1, 0 meaning the button is not pressed and 1 that the button is ...