I have been reading a book about crocheting models of hyperbolic planes.
Prior to this, I had never heard of hyperbolic planes, let alone considered crocheting models of them 
!
From reading the book I came to understand a bit about what they are and how & why crochet is a good medium for modeling them. I read about crocheting other mathematical/geometric concepts, too. And the thing is, we have been using these ideas in crochet for a long time without applying them to these other domains. So I found it all quite interesting.
I crocheted a small model of a hyperbolic plane and a small Möbius strip and made a hat.
These are the components
For those who are interested, this is the book
