I just watched a video about sha256 and it's internal workings. It's really incredible.
I'm really tempted to try and implement this from scratch.
https://www.youtube.com/watch?v=orIgy2MjqrA
You can even mine Bitcoin with pencil and paper: http://www.righto.com/2014/09/mining-bitcoin-with-pencil-and-paper.html?m=1
2
