I think crypto is possibly the best example in all of software development and/or computer science of how dangerous "unknown unknowns" are, and how a little kno

I think crypto is possibly the best example in all of software development and/or computer science of how dangerous "unknown unknowns" are, and how a little knowledge is a dangerous thing (although threads are a serious competitor for the latter trophy). I've studied cryptography theory, and I've implemented various ciphers and attacks, and the more I learn the more certain I become that I would never, ever use any of my own crypto code in production.