The setup is trivial. One Arduino Uno with pins in any of the analog capable ports connects to one LED on a breadboard through several resistors in series. The port is specified in line 104, at the instantiation time of the FireflyLED object; I used port 5.
The LED is the YSL-R531Y5C-5v yellow (585-595nm) LED from sparkfun.
I am really bad at reading resistor bands, but I've uploaded a picture of the resistors to this folder as well as a picture of the whole setup so it should be clear to anyone attempting to reproduce the setup.
Simply upload the code to the Uno and it will flash like a single frontalis: the brightness of the LED through the resistors in series seems to mimic the brightness of a firefly, but it's not precise.