The Slo-Mo Guys — a YouTube channel filled with fast things in slow motion — have a go at a hard drive. It's pretty amazing on its own — seeing that blurred, too-fast-to-follow arm slowed down is like kung-fu bullet-time for electronics. But once they start splashing water on the mechanism? Woah.
How a Hard Drive works in Slow Motion – The Slow Mo Guys
(Thanks, Fipi Lele!)