It all started with a small LCD salvaged from an old printer. I recruited Adam for some coding and we soon had the LCD displaying text from an Arduino microcontroller. This was neat, but it was inconvenient having to plug the Arduino into a computer for reprogramming whenever we wanted to change the text.

We needed something for inputting the text, and it didn’t take long to find a PS/2 keyboard code library for Arduino — confirming our observation that anything that communicates with wires has probably been hooked up to an Arduino. I salvaged a PS/2 port from an old computer motherboard, and after some trial and error, we could plug in a common PS/2 keyboard and type messages directly into the Arduino and out to the LCD.

The LCD was so small, however, that hardly anyone noticed our witty remarks. We needed a bigger display. After looking at many appallingly priced commercial LED matrix products, we found a new and much cheaper offering:

Sure Electronics’ 8×32 display boards. They cost $9 each and you can cascade up to four into one long display. We ordered three, and by the time they’d arrived, the Arduino community had already produced a library to run them. The result is our PS/2/You system, which displays keyboard-typed messages in 2"-tall LED letters that can be read from quite a distance. You can store and switch between six different lines of text, and it automatically scrolls through lines that are too long for the display. Power comes from an AC adapter or six AA batteries for portable operation, and the whole thing is housed in a sturdy wooden frame.

The uses for this contraption are many. Plug the keyboard in and enjoy putting your wittiest “wiseclacks” on it in the safety of your home, shop, or office, or use the battery option to take it into the wide world. We like to leave the keyboard accessible so that passers by can add a riposte or two to the dialogue, but if monologue is more your thing you can always take it elsewhere. Here's another idea: drill a broomstick-sized hole in the bottom of the frame and add a removable handle so you can wander the streets digitally promoting your geekified political leanings. Score keeping at sports events, birthday greetings, advertising your wares at a farmers market, beaming cryptic messages to your neighbours across the street – the possibilities are endless!

Check out the PS/2/You build tutorial as featured on Instructables and Make Magazine.