I've been subscribed to the Slow-Mo Guys' YouTube Channel for a few months now, ever since I noticed some of their great videos of random things that look quite interesting when recorded at over 1000 fps and played back in slow motion.
Their most recent video, How a Hard Drive Works (in Slow Motion) is one of my favorites, not because it's elaborate or amazing, but it's the first time I've ever actually seen the internals of a hard drive in operation. I've ripped apart a few hard drives in my day (they're built like tanks!), and they're amazing on the inside... but to see how quickly those read heads pop back and forth is amazing.
Sadly, as we've reached probably the pinnacle of mechanical design for spinning disk drives (I remember so many times having a hard drive randomly crash due to mechanical failure, but it's become a much rarer event), solid state drives are taking over. Therefore future generations will probably know as much about spinning disk drives as they do about record players and 8-track tapes. Oh well.