This is my 4500th post.
Here is a heat sink that I pulled out of a skip back in 1967 when I got my first job. Every year at Christmas it comes out of the bottom draw and sits on my desk at what ever place I am working at.
Each year I do something different with it. This year it has flashing LEDs on it controlled by an arduino. The USB connector is simply supplying power. There are two sequences each on lasting for 100 seconds. The first is a random flashing of each LED. Each LED has it's own independent period chosen at random between 1.5 seconds and 0.2 seconds. The second is a fixed pattern where the LEDs get lit in turn until they are all on and then turned off in turn.
A merry Christmas to you all. Or as I like to put it, have a good winter solstices celebration.
Ho ho ho ...... ;D