Space-filling curves, turning visual information into audio information, and the connection between infinite and finite math (this is a re-upload of an older video which had much worse audio).
Supplement with more space-filling curve fun: /watch?v=RU0wScIj36o
For more information on sight-via sound, this paper involving rewiring a ferret's retinas to its auditory cortex is particularly thought-provoking: http://phy.ucsf.edu/~houde/coleman/sur2.pdf
Alternatively, here is the NYT summary: https://goo.gl/qNuc14
Also, check out this excellent podcast on Human echolocation: https://goo.gl/23f4Yh
For anyone curious to read more about the connections between infinite and finite math, consider this Terry Tao blog post: https://goo.gl/NZ4yrW
Lion photo by Kevin Pluck
Music by Vincent Rubinetti: https://vincerubinetti.bandcamp.com/album/the-music-of-3blue1brown
3blue1brown is a channel about animating math, in all senses of the word animate. And you know the drill with YouTube, if you want to stay posted on new videos, subscribe, and click the bell to receive notifications (if you're into that).
If you are new to this channel and want to see more, a good place to start is this playlist: http://3b1b.co/recommended
Various social media stuffs: