Zodiac Killer: Code-breakers solve San Francisco killer's cipher

Previous submissions and discussions:

https://news.ycombinator.com/item?id=25397833

https://news.ycombinator.com/item?id=25397787

https://news.ycombinator.com/item?id=25397630

https://news.ycombinator.com/item?id=25396760

https://news.ycombinator.com/item?id=25396056

https://news.ycombinator.com/item?id=25393783

https://news.ycombinator.com/item?id=25392966

https://news.ycombinator.com/item?id=25392695

https://news.ycombinator.com/item?id=25391797

https://news.ycombinator.com/item?id=25391450

https://news.ycombinator.com/item?id=25391319 (3 comments)

https://news.ycombinator.com/item?id=25391065

https://news.ycombinator.com/item?id=25390960

https://news.ycombinator.com/item?id=25390941 (129 comments)

https://news.ycombinator.com/item?id=25389209 (3 comments)

https://news.ycombinator.com/item?id=25389164 (2 comments)

https://news.ycombinator.com/item?id=25387216 (8 comments)

There will probably be others that I've missed.