Morse code fascinates me, probably from a mix of a love for early electronic music and one-switch anything. It used to be a fairly established way of typing for one-switch users, and speeds of 20 words per minute or more are possible. I wonder what speeds are possible now with predictive text.
The top three videos link to war, but Morse code had far more altruistic origins. To simply bridge great distances so people could communicate with one another in a shared language. Some more links here: Morse translator and trainer, Morse Training by the Koch method, Raspberry Pi Project and a fairly bad three stooges joke.