Nerdy Christmas Lights

Matt Parker (Stand-up Maths): I wired my tree with 500 LED lights and calculated their 3D coordinates.. (YouTube, 24:37min)

Link and headline stolen from MetaFilter.
My favourite comment:

I’m surprised that he built a project involving lighting up a plane through a cone-shaped tree and didn’t mention conic sections. Missed opportunity, really.
It was a bit elliptic, so you might have missed it — but, between the hyperbole and the circular references, he did offer a parable about a cone and a plane.”