One of my earlier LED projects, Altared Space. My wife and I designed and built this piece, took it to Burning Man, assembled it, had our wedding ceremony in it, and then burned it to the ground (we saved the electronics though).
All told, it was some 1500 LEDs, 30 sheets of 3/4″ plywood, and a bunch of 2×4 and 4×4 to hold it all together. You can’t really see it in this photo, but the arches were laser etched to include images of things that were meaningful to us. The LEDs were driven by an Arduino Mega and randomly switched between about 10 different patterns. You could see the thing from miles away, assuming a dust storm wasn’t rolling through.
I’ll follow up with some posts regarding how this thing was made, and perhaps even link the code for the LEDs if I feel like starting a Github account.