Anyone watch Wintergatan? I've been watching his build videos religiously for years. Seriously, I usually watch a new video within a couple hours of it being posted.
channel link:
https://www.youtube.com/channel/UCcX...6_WqjkEniejRJQ
He's building a marble machine to play music. You may remember a viral video from years ago that did a similar thing with a much less impressive machine. The new machine is fantastic. If you're into it, you can go all the way back and watch the machine come together from the beginning.