For our Halloween party last year, we made this electronic fireplace to fit in with our cold color palette for the evening.
The form was made with some acrylic laser cut by the always talented Ronan, and I whipped some arduino code to blink the LEDs. The arduino has a few modes, each of which perform some simple algorithms on the current states of the lights to generate the next state. One mode runs some binary 1D cellular automata, to which it randomizes the generation rules. Feel free to modify this code for your own projects.