Solder wires from UBBB to LCD. (Note that uBBB pins are ordered as if looking at the bottom, since it also serves as a generic 32-TQFP breakout board if you flip it upside down). Specific connections are described below:

-Connect pins 1, 5, and 16 on the LCD, and connect all three to pin 3 (GND) on the uBBB

-Connect pin 2 (VDD) on the LCD to pin 4 (VCC) on the uBBB

-Connect pin 3 (VE) on the LCD to a potentiometer wiper between 5v and GND

-Connect pin 4 (RS) on the LCD to pin 15 (B1) on the uBBB

-Connect pin 6 (E) on the LCD to pin 16 (B2) on the uBBB

-Connect pins 11 .. 14 (Data 4 .. 7) on the LCD to pins 10 .. 13 (D4 .. D7) on the uBBB

-Connect pin 15 (A) on the LCD to pin 14 (B0) on the uBBB via a resistor (the resistor value picked will determine brightness, so experiment).

Cut out the box on your scroll saw or laser cutter, and put it together. If you cut it carefully enough you probably don't need any glue to hold it together; on mine, it is friction fit very nicely.

Put the electronics in the box. I used a couple dabs of hot glue to hold the uBBB and LCD in place (but not so much that you cannot take it out again if desired).

(Optionally) use some hot glue to attach velcro to the top of the box so that you can mount it underneath your monitor.

Customize and run the client program. I start mine from /etc/rc.local. It is written in such a way that it will continue to run even if the USB device is unplugged. (Other options would be to launch it from udev whenever the device is plugged in and kill it when it is unplugged... I tried it, but had some problems with udev matching multiple rules and running the program twice... I ended up just taking the easy way out.)